algorithm revision 1.1.1.1 1 // -*- C++ -*-
2 //===-------------------------- algorithm ---------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9
10 #ifndef _LIBCPP_ALGORITHM
11 #define _LIBCPP_ALGORITHM
12
13 /*
14 algorithm synopsis
15
16 #include <initializer_list>
17
18 namespace std
19 {
20
21 template <class InputIterator, class Predicate>
22 constexpr bool // constexpr in C++20
23 all_of(InputIterator first, InputIterator last, Predicate pred);
24
25 template <class InputIterator, class Predicate>
26 constexpr bool // constexpr in C++20
27 any_of(InputIterator first, InputIterator last, Predicate pred);
28
29 template <class InputIterator, class Predicate>
30 constexpr bool // constexpr in C++20
31 none_of(InputIterator first, InputIterator last, Predicate pred);
32
33 template <class InputIterator, class Function>
34 constexpr Function // constexpr in C++20
35 for_each(InputIterator first, InputIterator last, Function f);
36
37 template<class InputIterator, class Size, class Function>
38 constexpr InputIterator // constexpr in C++20
39 for_each_n(InputIterator first, Size n, Function f); // C++17
40
41 template <class InputIterator, class T>
42 constexpr InputIterator // constexpr in C++20
43 find(InputIterator first, InputIterator last, const T& value);
44
45 template <class InputIterator, class Predicate>
46 constexpr InputIterator // constexpr in C++20
47 find_if(InputIterator first, InputIterator last, Predicate pred);
48
49 template<class InputIterator, class Predicate>
50 constexpr InputIterator // constexpr in C++20
51 find_if_not(InputIterator first, InputIterator last, Predicate pred);
52
53 template <class ForwardIterator1, class ForwardIterator2>
54 constexpr ForwardIterator1 // constexpr in C++20
55 find_end(ForwardIterator1 first1, ForwardIterator1 last1,
56 ForwardIterator2 first2, ForwardIterator2 last2);
57
58 template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
59 constexpr ForwardIterator1 // constexpr in C++20
60 find_end(ForwardIterator1 first1, ForwardIterator1 last1,
61 ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
62
63 template <class ForwardIterator1, class ForwardIterator2>
64 constexpr ForwardIterator1 // constexpr in C++20
65 find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
66 ForwardIterator2 first2, ForwardIterator2 last2);
67
68 template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
69 constexpr ForwardIterator1 // constexpr in C++20
70 find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
71 ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
72
73 template <class ForwardIterator>
74 constexpr ForwardIterator // constexpr in C++20
75 adjacent_find(ForwardIterator first, ForwardIterator last);
76
77 template <class ForwardIterator, class BinaryPredicate>
78 constexpr ForwardIterator // constexpr in C++20
79 adjacent_find(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
80
81 template <class InputIterator, class T>
82 constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
83 count(InputIterator first, InputIterator last, const T& value);
84
85 template <class InputIterator, class Predicate>
86 constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
87 count_if(InputIterator first, InputIterator last, Predicate pred);
88
89 template <class InputIterator1, class InputIterator2>
90 constexpr pair<InputIterator1, InputIterator2> // constexpr in C++20
91 mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
92
93 template <class InputIterator1, class InputIterator2>
94 constexpr pair<InputIterator1, InputIterator2> // constexpr in C++20
95 mismatch(InputIterator1 first1, InputIterator1 last1,
96 InputIterator2 first2, InputIterator2 last2); // **C++14**
97
98 template <class InputIterator1, class InputIterator2, class BinaryPredicate>
99 constexpr pair<InputIterator1, InputIterator2> // constexpr in C++20
100 mismatch(InputIterator1 first1, InputIterator1 last1,
101 InputIterator2 first2, BinaryPredicate pred);
102
103 template <class InputIterator1, class InputIterator2, class BinaryPredicate>
104 constexpr pair<InputIterator1, InputIterator2> // constexpr in C++20
105 mismatch(InputIterator1 first1, InputIterator1 last1,
106 InputIterator2 first2, InputIterator2 last2,
107 BinaryPredicate pred); // **C++14**
108
109 template <class InputIterator1, class InputIterator2>
110 constexpr bool // constexpr in C++20
111 equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
112
113 template <class InputIterator1, class InputIterator2>
114 constexpr bool // constexpr in C++20
115 equal(InputIterator1 first1, InputIterator1 last1,
116 InputIterator2 first2, InputIterator2 last2); // **C++14**
117
118 template <class InputIterator1, class InputIterator2, class BinaryPredicate>
119 constexpr bool // constexpr in C++20
120 equal(InputIterator1 first1, InputIterator1 last1,
121 InputIterator2 first2, BinaryPredicate pred);
122
123 template <class InputIterator1, class InputIterator2, class BinaryPredicate>
124 constexpr bool // constexpr in C++20
125 equal(InputIterator1 first1, InputIterator1 last1,
126 InputIterator2 first2, InputIterator2 last2,
127 BinaryPredicate pred); // **C++14**
128
129 template<class ForwardIterator1, class ForwardIterator2>
130 constexpr bool // constexpr in C++20
131 is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
132 ForwardIterator2 first2);
133
134 template<class ForwardIterator1, class ForwardIterator2>
135 constexpr bool // constexpr in C++20
136 is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
137 ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
138
139 template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
140 constexpr bool // constexpr in C++20
141 is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
142 ForwardIterator2 first2, BinaryPredicate pred);
143
144 template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
145 constexpr bool // constexpr in C++20
146 is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
147 ForwardIterator2 first2, ForwardIterator2 last2,
148 BinaryPredicate pred); // **C++14**
149
150 template <class ForwardIterator1, class ForwardIterator2>
151 constexpr ForwardIterator1 // constexpr in C++20
152 search(ForwardIterator1 first1, ForwardIterator1 last1,
153 ForwardIterator2 first2, ForwardIterator2 last2);
154
155 template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
156 constexpr ForwardIterator1 // constexpr in C++20
157 search(ForwardIterator1 first1, ForwardIterator1 last1,
158 ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
159
160 template <class ForwardIterator, class Size, class T>
161 constexpr ForwardIterator // constexpr in C++20
162 search_n(ForwardIterator first, ForwardIterator last, Size count, const T& value);
163
164 template <class ForwardIterator, class Size, class T, class BinaryPredicate>
165 constexpr ForwardIterator // constexpr in C++20
166 search_n(ForwardIterator first, ForwardIterator last,
167 Size count, const T& value, BinaryPredicate pred);
168
169 template <class InputIterator, class OutputIterator>
170 constexpr OutputIterator // constexpr in C++20
171 copy(InputIterator first, InputIterator last, OutputIterator result);
172
173 template<class InputIterator, class OutputIterator, class Predicate>
174 constexpr OutputIterator // constexpr in C++20
175 copy_if(InputIterator first, InputIterator last,
176 OutputIterator result, Predicate pred);
177
178 template<class InputIterator, class Size, class OutputIterator>
179 constexpr OutputIterator // constexpr in C++20
180 copy_n(InputIterator first, Size n, OutputIterator result);
181
182 template <class BidirectionalIterator1, class BidirectionalIterator2>
183 constexpr BidirectionalIterator2 // constexpr in C++20
184 copy_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
185 BidirectionalIterator2 result);
186
187 template <class ForwardIterator1, class ForwardIterator2>
188 constexpr ForwardIterator2 // constexpr in C++20
189 swap_ranges(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2);
190
191 template <class ForwardIterator1, class ForwardIterator2>
192 constexpr void // constexpr in C++20
193 iter_swap(ForwardIterator1 a, ForwardIterator2 b);
194
195 template <class InputIterator, class OutputIterator, class UnaryOperation>
196 constexpr OutputIterator // constexpr in C++20
197 transform(InputIterator first, InputIterator last, OutputIterator result, UnaryOperation op);
198
199 template <class InputIterator1, class InputIterator2, class OutputIterator, class BinaryOperation>
200 constexpr OutputIterator // constexpr in C++20
201 transform(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2,
202 OutputIterator result, BinaryOperation binary_op);
203
204 template <class ForwardIterator, class T>
205 constexpr void // constexpr in C++20
206 replace(ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value);
207
208 template <class ForwardIterator, class Predicate, class T>
209 constexpr void // constexpr in C++20
210 replace_if(ForwardIterator first, ForwardIterator last, Predicate pred, const T& new_value);
211
212 template <class InputIterator, class OutputIterator, class T>
213 constexpr OutputIterator // constexpr in C++20
214 replace_copy(InputIterator first, InputIterator last, OutputIterator result,
215 const T& old_value, const T& new_value);
216
217 template <class InputIterator, class OutputIterator, class Predicate, class T>
218 constexpr OutputIterator // constexpr in C++20
219 replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T& new_value);
220
221 template <class ForwardIterator, class T>
222 constexpr void // constexpr in C++20
223 fill(ForwardIterator first, ForwardIterator last, const T& value);
224
225 template <class OutputIterator, class Size, class T>
226 constexpr OutputIterator // constexpr in C++20
227 fill_n(OutputIterator first, Size n, const T& value);
228
229 template <class ForwardIterator, class Generator>
230 constexpr void // constexpr in C++20
231 generate(ForwardIterator first, ForwardIterator last, Generator gen);
232
233 template <class OutputIterator, class Size, class Generator>
234 constexpr OutputIterator // constexpr in C++20
235 generate_n(OutputIterator first, Size n, Generator gen);
236
237 template <class ForwardIterator, class T>
238 constexpr ForwardIterator // constexpr in C++20
239 remove(ForwardIterator first, ForwardIterator last, const T& value);
240
241 template <class ForwardIterator, class Predicate>
242 constexpr ForwardIterator // constexpr in C++20
243 remove_if(ForwardIterator first, ForwardIterator last, Predicate pred);
244
245 template <class InputIterator, class OutputIterator, class T>
246 constexpr OutputIterator // constexpr in C++20
247 remove_copy(InputIterator first, InputIterator last, OutputIterator result, const T& value);
248
249 template <class InputIterator, class OutputIterator, class Predicate>
250 constexpr OutputIterator // constexpr in C++20
251 remove_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred);
252
253 template <class ForwardIterator>
254 constexpr ForwardIterator // constexpr in C++20
255 unique(ForwardIterator first, ForwardIterator last);
256
257 template <class ForwardIterator, class BinaryPredicate>
258 constexpr ForwardIterator // constexpr in C++20
259 unique(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
260
261 template <class InputIterator, class OutputIterator>
262 constexpr OutputIterator // constexpr in C++20
263 unique_copy(InputIterator first, InputIterator last, OutputIterator result);
264
265 template <class InputIterator, class OutputIterator, class BinaryPredicate>
266 constexpr OutputIterator // constexpr in C++20
267 unique_copy(InputIterator first, InputIterator last, OutputIterator result, BinaryPredicate pred);
268
269 template <class BidirectionalIterator>
270 constexpr void // constexpr in C++20
271 reverse(BidirectionalIterator first, BidirectionalIterator last);
272
273 template <class BidirectionalIterator, class OutputIterator>
274 constexpr OutputIterator // constexpr in C++20
275 reverse_copy(BidirectionalIterator first, BidirectionalIterator last, OutputIterator result);
276
277 template <class ForwardIterator>
278 constexpr ForwardIterator // constexpr in C++20
279 rotate(ForwardIterator first, ForwardIterator middle, ForwardIterator last);
280
281 template <class ForwardIterator, class OutputIterator>
282 constexpr OutputIterator // constexpr in C++20
283 rotate_copy(ForwardIterator first, ForwardIterator middle, ForwardIterator last, OutputIterator result);
284
285 template <class RandomAccessIterator>
286 void
287 random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14, removed in C++17
288
289 template <class RandomAccessIterator, class RandomNumberGenerator>
290 void
291 random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
292 RandomNumberGenerator& rand); // deprecated in C++14, removed in C++17
293
294 template<class PopulationIterator, class SampleIterator,
295 class Distance, class UniformRandomBitGenerator>
296 SampleIterator sample(PopulationIterator first, PopulationIterator last,
297 SampleIterator out, Distance n,
298 UniformRandomBitGenerator&& g); // C++17
299
300 template<class RandomAccessIterator, class UniformRandomNumberGenerator>
301 void shuffle(RandomAccessIterator first, RandomAccessIterator last,
302 UniformRandomNumberGenerator&& g);
303
304 template<class ForwardIterator>
305 constexpr ForwardIterator
306 shift_left(ForwardIterator first, ForwardIterator last,
307 typename iterator_traits<ForwardIterator>::difference_type n); // C++20
308
309 template<class ForwardIterator>
310 constexpr ForwardIterator
311 shift_right(ForwardIterator first, ForwardIterator last,
312 typename iterator_traits<ForwardIterator>::difference_type n); // C++20
313
314 template <class InputIterator, class Predicate>
315 constexpr bool // constexpr in C++20
316 is_partitioned(InputIterator first, InputIterator last, Predicate pred);
317
318 template <class ForwardIterator, class Predicate>
319 constexpr ForwardIterator // constexpr in C++20
320 partition(ForwardIterator first, ForwardIterator last, Predicate pred);
321
322 template <class InputIterator, class OutputIterator1,
323 class OutputIterator2, class Predicate>
324 constexpr pair<OutputIterator1, OutputIterator2> // constexpr in C++20
325 partition_copy(InputIterator first, InputIterator last,
326 OutputIterator1 out_true, OutputIterator2 out_false,
327 Predicate pred);
328
329 template <class ForwardIterator, class Predicate>
330 ForwardIterator
331 stable_partition(ForwardIterator first, ForwardIterator last, Predicate pred);
332
333 template<class ForwardIterator, class Predicate>
334 constexpr ForwardIterator // constexpr in C++20
335 partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
336
337 template <class ForwardIterator>
338 constexpr bool // constexpr in C++20
339 is_sorted(ForwardIterator first, ForwardIterator last);
340
341 template <class ForwardIterator, class Compare>
342 constexpr bool // constexpr in C++20
343 is_sorted(ForwardIterator first, ForwardIterator last, Compare comp);
344
345 template<class ForwardIterator>
346 constexpr ForwardIterator // constexpr in C++20
347 is_sorted_until(ForwardIterator first, ForwardIterator last);
348
349 template <class ForwardIterator, class Compare>
350 constexpr ForwardIterator // constexpr in C++20
351 is_sorted_until(ForwardIterator first, ForwardIterator last, Compare comp);
352
353 template <class RandomAccessIterator>
354 constexpr void // constexpr in C++20
355 sort(RandomAccessIterator first, RandomAccessIterator last);
356
357 template <class RandomAccessIterator, class Compare>
358 constexpr void // constexpr in C++20
359 sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
360
361 template <class RandomAccessIterator>
362 void
363 stable_sort(RandomAccessIterator first, RandomAccessIterator last);
364
365 template <class RandomAccessIterator, class Compare>
366 void
367 stable_sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
368
369 template <class RandomAccessIterator>
370 constexpr void // constexpr in C++20
371 partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last);
372
373 template <class RandomAccessIterator, class Compare>
374 constexpr void // constexpr in C++20
375 partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last, Compare comp);
376
377 template <class InputIterator, class RandomAccessIterator>
378 constexpr RandomAccessIterator // constexpr in C++20
379 partial_sort_copy(InputIterator first, InputIterator last,
380 RandomAccessIterator result_first, RandomAccessIterator result_last);
381
382 template <class InputIterator, class RandomAccessIterator, class Compare>
383 constexpr RandomAccessIterator // constexpr in C++20
384 partial_sort_copy(InputIterator first, InputIterator last,
385 RandomAccessIterator result_first, RandomAccessIterator result_last, Compare comp);
386
387 template <class RandomAccessIterator>
388 constexpr void // constexpr in C++20
389 nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last);
390
391 template <class RandomAccessIterator, class Compare>
392 constexpr void // constexpr in C++20
393 nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last, Compare comp);
394
395 template <class ForwardIterator, class T>
396 constexpr ForwardIterator // constexpr in C++20
397 lower_bound(ForwardIterator first, ForwardIterator last, const T& value);
398
399 template <class ForwardIterator, class T, class Compare>
400 constexpr ForwardIterator // constexpr in C++20
401 lower_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
402
403 template <class ForwardIterator, class T>
404 constexpr ForwardIterator // constexpr in C++20
405 upper_bound(ForwardIterator first, ForwardIterator last, const T& value);
406
407 template <class ForwardIterator, class T, class Compare>
408 constexpr ForwardIterator // constexpr in C++20
409 upper_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
410
411 template <class ForwardIterator, class T>
412 constexpr pair<ForwardIterator, ForwardIterator> // constexpr in C++20
413 equal_range(ForwardIterator first, ForwardIterator last, const T& value);
414
415 template <class ForwardIterator, class T, class Compare>
416 constexpr pair<ForwardIterator, ForwardIterator> // constexpr in C++20
417 equal_range(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
418
419 template <class ForwardIterator, class T>
420 constexpr bool // constexpr in C++20
421 binary_search(ForwardIterator first, ForwardIterator last, const T& value);
422
423 template <class ForwardIterator, class T, class Compare>
424 constexpr bool // constexpr in C++20
425 binary_search(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
426
427 template <class InputIterator1, class InputIterator2, class OutputIterator>
428 constexpr OutputIterator // constexpr in C++20
429 merge(InputIterator1 first1, InputIterator1 last1,
430 InputIterator2 first2, InputIterator2 last2, OutputIterator result);
431
432 template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
433 constexpr OutputIterator // constexpr in C++20
434 merge(InputIterator1 first1, InputIterator1 last1,
435 InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
436
437 template <class BidirectionalIterator>
438 void
439 inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last);
440
441 template <class BidirectionalIterator, class Compare>
442 void
443 inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last, Compare comp);
444
445 template <class InputIterator1, class InputIterator2>
446 constexpr bool // constexpr in C++20
447 includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
448
449 template <class InputIterator1, class InputIterator2, class Compare>
450 constexpr bool // constexpr in C++20
451 includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, Compare comp);
452
453 template <class InputIterator1, class InputIterator2, class OutputIterator>
454 constexpr OutputIterator // constexpr in C++20
455 set_union(InputIterator1 first1, InputIterator1 last1,
456 InputIterator2 first2, InputIterator2 last2, OutputIterator result);
457
458 template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
459 constexpr OutputIterator // constexpr in C++20
460 set_union(InputIterator1 first1, InputIterator1 last1,
461 InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
462
463 template <class InputIterator1, class InputIterator2, class OutputIterator>
464 constexpr OutputIterator // constexpr in C++20
465 set_intersection(InputIterator1 first1, InputIterator1 last1,
466 InputIterator2 first2, InputIterator2 last2, OutputIterator result);
467
468 template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
469 constexpr OutputIterator // constexpr in C++20
470 set_intersection(InputIterator1 first1, InputIterator1 last1,
471 InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
472
473 template <class InputIterator1, class InputIterator2, class OutputIterator>
474 constexpr OutputIterator // constexpr in C++20
475 set_difference(InputIterator1 first1, InputIterator1 last1,
476 InputIterator2 first2, InputIterator2 last2, OutputIterator result);
477
478 template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
479 constexpr OutputIterator // constexpr in C++20
480 set_difference(InputIterator1 first1, InputIterator1 last1,
481 InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
482
483 template <class InputIterator1, class InputIterator2, class OutputIterator>
484 constexpr OutputIterator // constexpr in C++20
485 set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
486 InputIterator2 first2, InputIterator2 last2, OutputIterator result);
487
488 template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
489 constexpr OutputIterator // constexpr in C++20
490 set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
491 InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
492
493 template <class RandomAccessIterator>
494 constexpr void // constexpr in C++20
495 push_heap(RandomAccessIterator first, RandomAccessIterator last);
496
497 template <class RandomAccessIterator, class Compare>
498 constexpr void // constexpr in C++20
499 push_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
500
501 template <class RandomAccessIterator>
502 constexpr void // constexpr in C++20
503 pop_heap(RandomAccessIterator first, RandomAccessIterator last);
504
505 template <class RandomAccessIterator, class Compare>
506 constexpr void // constexpr in C++20
507 pop_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
508
509 template <class RandomAccessIterator>
510 constexpr void // constexpr in C++20
511 make_heap(RandomAccessIterator first, RandomAccessIterator last);
512
513 template <class RandomAccessIterator, class Compare>
514 constexpr void // constexpr in C++20
515 make_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
516
517 template <class RandomAccessIterator>
518 constexpr void // constexpr in C++20
519 sort_heap(RandomAccessIterator first, RandomAccessIterator last);
520
521 template <class RandomAccessIterator, class Compare>
522 constexpr void // constexpr in C++20
523 sort_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
524
525 template <class RandomAccessIterator>
526 constexpr bool // constexpr in C++20
527 is_heap(RandomAccessIterator first, RandomAccessiterator last);
528
529 template <class RandomAccessIterator, class Compare>
530 constexpr bool // constexpr in C++20
531 is_heap(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
532
533 template <class RandomAccessIterator>
534 constexpr RandomAccessIterator // constexpr in C++20
535 is_heap_until(RandomAccessIterator first, RandomAccessiterator last);
536
537 template <class RandomAccessIterator, class Compare>
538 constexpr RandomAccessIterator // constexpr in C++20
539 is_heap_until(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
540
541 template <class ForwardIterator>
542 constexpr ForwardIterator // constexpr in C++14
543 min_element(ForwardIterator first, ForwardIterator last);
544
545 template <class ForwardIterator, class Compare>
546 constexpr ForwardIterator // constexpr in C++14
547 min_element(ForwardIterator first, ForwardIterator last, Compare comp);
548
549 template <class T>
550 constexpr const T& // constexpr in C++14
551 min(const T& a, const T& b);
552
553 template <class T, class Compare>
554 constexpr const T& // constexpr in C++14
555 min(const T& a, const T& b, Compare comp);
556
557 template<class T>
558 constexpr T // constexpr in C++14
559 min(initializer_list<T> t);
560
561 template<class T, class Compare>
562 constexpr T // constexpr in C++14
563 min(initializer_list<T> t, Compare comp);
564
565 template<class T>
566 constexpr const T& clamp(const T& v, const T& lo, const T& hi); // C++17
567
568 template<class T, class Compare>
569 constexpr const T& clamp(const T& v, const T& lo, const T& hi, Compare comp); // C++17
570
571 template <class ForwardIterator>
572 constexpr ForwardIterator // constexpr in C++14
573 max_element(ForwardIterator first, ForwardIterator last);
574
575 template <class ForwardIterator, class Compare>
576 constexpr ForwardIterator // constexpr in C++14
577 max_element(ForwardIterator first, ForwardIterator last, Compare comp);
578
579 template <class T>
580 constexpr const T& // constexpr in C++14
581 max(const T& a, const T& b);
582
583 template <class T, class Compare>
584 constexpr const T& // constexpr in C++14
585 max(const T& a, const T& b, Compare comp);
586
587 template<class T>
588 constexpr T // constexpr in C++14
589 max(initializer_list<T> t);
590
591 template<class T, class Compare>
592 constexpr T // constexpr in C++14
593 max(initializer_list<T> t, Compare comp);
594
595 template<class ForwardIterator>
596 constexpr pair<ForwardIterator, ForwardIterator> // constexpr in C++14
597 minmax_element(ForwardIterator first, ForwardIterator last);
598
599 template<class ForwardIterator, class Compare>
600 constexpr pair<ForwardIterator, ForwardIterator> // constexpr in C++14
601 minmax_element(ForwardIterator first, ForwardIterator last, Compare comp);
602
603 template<class T>
604 constexpr pair<const T&, const T&> // constexpr in C++14
605 minmax(const T& a, const T& b);
606
607 template<class T, class Compare>
608 constexpr pair<const T&, const T&> // constexpr in C++14
609 minmax(const T& a, const T& b, Compare comp);
610
611 template<class T>
612 constexpr pair<T, T> // constexpr in C++14
613 minmax(initializer_list<T> t);
614
615 template<class T, class Compare>
616 constexpr pair<T, T> // constexpr in C++14
617 minmax(initializer_list<T> t, Compare comp);
618
619 template <class InputIterator1, class InputIterator2>
620 constexpr bool // constexpr in C++20
621 lexicographical_compare(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
622
623 template <class InputIterator1, class InputIterator2, class Compare>
624 constexpr bool // constexpr in C++20
625 lexicographical_compare(InputIterator1 first1, InputIterator1 last1,
626 InputIterator2 first2, InputIterator2 last2, Compare comp);
627
628 template <class BidirectionalIterator>
629 constexpr bool // constexpr in C++20
630 next_permutation(BidirectionalIterator first, BidirectionalIterator last);
631
632 template <class BidirectionalIterator, class Compare>
633 constexpr bool // constexpr in C++20
634 next_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
635
636 template <class BidirectionalIterator>
637 constexpr bool // constexpr in C++20
638 prev_permutation(BidirectionalIterator first, BidirectionalIterator last);
639
640 template <class BidirectionalIterator, class Compare>
641 constexpr bool // constexpr in C++20
642 prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
643
644 } // std
645
646 */
647
648 #include <__config>
649 #include <initializer_list>
650 #include <type_traits>
651 #include <cstring>
652 #include <utility> // needed to provide swap_ranges.
653 #include <memory>
654 #include <functional>
655 #include <iterator>
656 #include <cstddef>
657 #include <bit>
658 #include <version>
659
660 #include <__debug>
661
662 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
663 #pragma GCC system_header
664 #endif
665
666 _LIBCPP_PUSH_MACROS
667 #include <__undef_macros>
668
669
670 _LIBCPP_BEGIN_NAMESPACE_STD
671
672 // I'd like to replace these with _VSTD::equal_to<void>, but can't because:
673 // * That only works with C++14 and later, and
674 // * We haven't included <functional> here.
675 template <class _T1, class _T2 = _T1>
676 struct __equal_to
677 {
678 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
679 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T1& __x, const _T2& __y) const {return __x == __y;}
680 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T2& __x, const _T1& __y) const {return __x == __y;}
681 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T2& __x, const _T2& __y) const {return __x == __y;}
682 };
683
684 template <class _T1>
685 struct __equal_to<_T1, _T1>
686 {
687 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
688 bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
689 };
690
691 template <class _T1>
692 struct __equal_to<const _T1, _T1>
693 {
694 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
695 bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
696 };
697
698 template <class _T1>
699 struct __equal_to<_T1, const _T1>
700 {
701 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
702 bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
703 };
704
705 template <class _T1, class _T2 = _T1>
706 struct __less
707 {
708 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
709 bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
710
711 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
712 bool operator()(const _T1& __x, const _T2& __y) const {return __x < __y;}
713
714 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
715 bool operator()(const _T2& __x, const _T1& __y) const {return __x < __y;}
716
717 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
718 bool operator()(const _T2& __x, const _T2& __y) const {return __x < __y;}
719 };
720
721 template <class _T1>
722 struct __less<_T1, _T1>
723 {
724 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
725 bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
726 };
727
728 template <class _T1>
729 struct __less<const _T1, _T1>
730 {
731 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
732 bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
733 };
734
735 template <class _T1>
736 struct __less<_T1, const _T1>
737 {
738 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
739 bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
740 };
741
742 template <class _Predicate>
743 class __invert // invert the sense of a comparison
744 {
745 private:
746 _Predicate __p_;
747 public:
748 _LIBCPP_INLINE_VISIBILITY __invert() {}
749
750 _LIBCPP_INLINE_VISIBILITY
751 explicit __invert(_Predicate __p) : __p_(__p) {}
752
753 template <class _T1>
754 _LIBCPP_INLINE_VISIBILITY
755 bool operator()(const _T1& __x) {return !__p_(__x);}
756
757 template <class _T1, class _T2>
758 _LIBCPP_INLINE_VISIBILITY
759 bool operator()(const _T1& __x, const _T2& __y) {return __p_(__y, __x);}
760 };
761
762 // Perform division by two quickly for positive integers (llvm.org/PR39129)
763
764 template <typename _Integral>
765 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
766 typename enable_if
767 <
768 is_integral<_Integral>::value,
769 _Integral
770 >::type
771 __half_positive(_Integral __value)
772 {
773 return static_cast<_Integral>(static_cast<typename make_unsigned<_Integral>::type>(__value) / 2);
774 }
775
776 template <typename _Tp>
777 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
778 typename enable_if
779 <
780 !is_integral<_Tp>::value,
781 _Tp
782 >::type
783 __half_positive(_Tp __value)
784 {
785 return __value / 2;
786 }
787
788 #ifdef _LIBCPP_DEBUG
789
790 template <class _Compare>
791 struct __debug_less
792 {
793 _Compare &__comp_;
794 _LIBCPP_CONSTEXPR_AFTER_CXX17
795 __debug_less(_Compare& __c) : __comp_(__c) {}
796
797 template <class _Tp, class _Up>
798 _LIBCPP_CONSTEXPR_AFTER_CXX17
799 bool operator()(const _Tp& __x, const _Up& __y)
800 {
801 bool __r = __comp_(__x, __y);
802 if (__r)
803 __do_compare_assert(0, __y, __x);
804 return __r;
805 }
806
807 template <class _Tp, class _Up>
808 _LIBCPP_CONSTEXPR_AFTER_CXX17
809 bool operator()(_Tp& __x, _Up& __y)
810 {
811 bool __r = __comp_(__x, __y);
812 if (__r)
813 __do_compare_assert(0, __y, __x);
814 return __r;
815 }
816
817 template <class _LHS, class _RHS>
818 _LIBCPP_CONSTEXPR_AFTER_CXX17
819 inline _LIBCPP_INLINE_VISIBILITY
820 decltype((void)declval<_Compare&>()(
821 declval<_LHS &>(), declval<_RHS &>()))
822 __do_compare_assert(int, _LHS & __l, _RHS & __r) {
823 _LIBCPP_ASSERT(!__comp_(__l, __r),
824 "Comparator does not induce a strict weak ordering");
825 }
826
827 template <class _LHS, class _RHS>
828 _LIBCPP_CONSTEXPR_AFTER_CXX17
829 inline _LIBCPP_INLINE_VISIBILITY
830 void __do_compare_assert(long, _LHS &, _RHS &) {}
831 };
832
833 #endif // _LIBCPP_DEBUG
834
835 template <class _Comp>
836 struct __comp_ref_type {
837 // Pass the comparator by lvalue reference. Or in debug mode, using a
838 // debugging wrapper that stores a reference.
839 #ifndef _LIBCPP_DEBUG
840 typedef typename add_lvalue_reference<_Comp>::type type;
841 #else
842 typedef __debug_less<_Comp> type;
843 #endif
844 };
845
846 // all_of
847
848 template <class _InputIterator, class _Predicate>
849 _LIBCPP_NODISCARD_EXT inline
850 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
851 bool
852 all_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
853 {
854 for (; __first != __last; ++__first)
855 if (!__pred(*__first))
856 return false;
857 return true;
858 }
859
860 // any_of
861
862 template <class _InputIterator, class _Predicate>
863 _LIBCPP_NODISCARD_EXT inline
864 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
865 bool
866 any_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
867 {
868 for (; __first != __last; ++__first)
869 if (__pred(*__first))
870 return true;
871 return false;
872 }
873
874 // none_of
875
876 template <class _InputIterator, class _Predicate>
877 _LIBCPP_NODISCARD_EXT inline
878 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
879 bool
880 none_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
881 {
882 for (; __first != __last; ++__first)
883 if (__pred(*__first))
884 return false;
885 return true;
886 }
887
888 // for_each
889
890 template <class _InputIterator, class _Function>
891 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
892 _Function
893 for_each(_InputIterator __first, _InputIterator __last, _Function __f)
894 {
895 for (; __first != __last; ++__first)
896 __f(*__first);
897 return __f;
898 }
899
900 #if _LIBCPP_STD_VER > 14
901 // for_each_n
902
903 template <class _InputIterator, class _Size, class _Function>
904 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
905 _InputIterator
906 for_each_n(_InputIterator __first, _Size __orig_n, _Function __f)
907 {
908 typedef decltype(_VSTD::__convert_to_integral(__orig_n)) _IntegralSize;
909 _IntegralSize __n = __orig_n;
910 while (__n > 0)
911 {
912 __f(*__first);
913 ++__first;
914 --__n;
915 }
916 return __first;
917 }
918 #endif
919
920 // find
921
922 template <class _InputIterator, class _Tp>
923 _LIBCPP_NODISCARD_EXT inline
924 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
925 _InputIterator
926 find(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
927 {
928 for (; __first != __last; ++__first)
929 if (*__first == __value_)
930 break;
931 return __first;
932 }
933
934 // find_if
935
936 template <class _InputIterator, class _Predicate>
937 _LIBCPP_NODISCARD_EXT inline
938 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
939 _InputIterator
940 find_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
941 {
942 for (; __first != __last; ++__first)
943 if (__pred(*__first))
944 break;
945 return __first;
946 }
947
948 // find_if_not
949
950 template<class _InputIterator, class _Predicate>
951 _LIBCPP_NODISCARD_EXT inline
952 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
953 _InputIterator
954 find_if_not(_InputIterator __first, _InputIterator __last, _Predicate __pred)
955 {
956 for (; __first != __last; ++__first)
957 if (!__pred(*__first))
958 break;
959 return __first;
960 }
961
962 // find_end
963
964 template <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
965 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator1
966 __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
967 _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred,
968 forward_iterator_tag, forward_iterator_tag)
969 {
970 // modeled after search algorithm
971 _ForwardIterator1 __r = __last1; // __last1 is the "default" answer
972 if (__first2 == __last2)
973 return __r;
974 while (true)
975 {
976 while (true)
977 {
978 if (__first1 == __last1) // if source exhausted return last correct answer
979 return __r; // (or __last1 if never found)
980 if (__pred(*__first1, *__first2))
981 break;
982 ++__first1;
983 }
984 // *__first1 matches *__first2, now match elements after here
985 _ForwardIterator1 __m1 = __first1;
986 _ForwardIterator2 __m2 = __first2;
987 while (true)
988 {
989 if (++__m2 == __last2)
990 { // Pattern exhaused, record answer and search for another one
991 __r = __first1;
992 ++__first1;
993 break;
994 }
995 if (++__m1 == __last1) // Source exhausted, return last answer
996 return __r;
997 if (!__pred(*__m1, *__m2)) // mismatch, restart with a new __first
998 {
999 ++__first1;
1000 break;
1001 } // else there is a match, check next elements
1002 }
1003 }
1004 }
1005
1006 template <class _BinaryPredicate, class _BidirectionalIterator1, class _BidirectionalIterator2>
1007 _LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator1
1008 __find_end(_BidirectionalIterator1 __first1, _BidirectionalIterator1 __last1,
1009 _BidirectionalIterator2 __first2, _BidirectionalIterator2 __last2, _BinaryPredicate __pred,
1010 bidirectional_iterator_tag, bidirectional_iterator_tag)
1011 {
1012 // modeled after search algorithm (in reverse)
1013 if (__first2 == __last2)
1014 return __last1; // Everything matches an empty sequence
1015 _BidirectionalIterator1 __l1 = __last1;
1016 _BidirectionalIterator2 __l2 = __last2;
1017 --__l2;
1018 while (true)
1019 {
1020 // Find last element in sequence 1 that matchs *(__last2-1), with a mininum of loop checks
1021 while (true)
1022 {
1023 if (__first1 == __l1) // return __last1 if no element matches *__first2
1024 return __last1;
1025 if (__pred(*--__l1, *__l2))
1026 break;
1027 }
1028 // *__l1 matches *__l2, now match elements before here
1029 _BidirectionalIterator1 __m1 = __l1;
1030 _BidirectionalIterator2 __m2 = __l2;
1031 while (true)
1032 {
1033 if (__m2 == __first2) // If pattern exhausted, __m1 is the answer (works for 1 element pattern)
1034 return __m1;
1035 if (__m1 == __first1) // Otherwise if source exhaused, pattern not found
1036 return __last1;
1037 if (!__pred(*--__m1, *--__m2)) // if there is a mismatch, restart with a new __l1
1038 {
1039 break;
1040 } // else there is a match, check next elements
1041 }
1042 }
1043 }
1044
1045 template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
1046 _LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator1
1047 __find_end(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
1048 _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
1049 random_access_iterator_tag, random_access_iterator_tag)
1050 {
1051 // Take advantage of knowing source and pattern lengths. Stop short when source is smaller than pattern
1052 typename iterator_traits<_RandomAccessIterator2>::difference_type __len2 = __last2 - __first2;
1053 if (__len2 == 0)
1054 return __last1;
1055 typename iterator_traits<_RandomAccessIterator1>::difference_type __len1 = __last1 - __first1;
1056 if (__len1 < __len2)
1057 return __last1;
1058 const _RandomAccessIterator1 __s = __first1 + (__len2 - 1); // End of pattern match can't go before here
1059 _RandomAccessIterator1 __l1 = __last1;
1060 _RandomAccessIterator2 __l2 = __last2;
1061 --__l2;
1062 while (true)
1063 {
1064 while (true)
1065 {
1066 if (__s == __l1)
1067 return __last1;
1068 if (__pred(*--__l1, *__l2))
1069 break;
1070 }
1071 _RandomAccessIterator1 __m1 = __l1;
1072 _RandomAccessIterator2 __m2 = __l2;
1073 while (true)
1074 {
1075 if (__m2 == __first2)
1076 return __m1;
1077 // no need to check range on __m1 because __s guarantees we have enough source
1078 if (!__pred(*--__m1, *--__m2))
1079 {
1080 break;
1081 }
1082 }
1083 }
1084 }
1085
1086 template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
1087 _LIBCPP_NODISCARD_EXT inline
1088 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1089 _ForwardIterator1
1090 find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1091 _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
1092 {
1093 return _VSTD::__find_end<typename add_lvalue_reference<_BinaryPredicate>::type>
1094 (__first1, __last1, __first2, __last2, __pred,
1095 typename iterator_traits<_ForwardIterator1>::iterator_category(),
1096 typename iterator_traits<_ForwardIterator2>::iterator_category());
1097 }
1098
1099 template <class _ForwardIterator1, class _ForwardIterator2>
1100 _LIBCPP_NODISCARD_EXT inline
1101 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1102 _ForwardIterator1
1103 find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1104 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
1105 {
1106 typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
1107 typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1108 return _VSTD::find_end(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
1109 }
1110
1111 // find_first_of
1112
1113 template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
1114 _LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator1
1115 __find_first_of_ce(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1116 _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
1117 {
1118 for (; __first1 != __last1; ++__first1)
1119 for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
1120 if (__pred(*__first1, *__j))
1121 return __first1;
1122 return __last1;
1123 }
1124
1125
1126 template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
1127 _LIBCPP_NODISCARD_EXT inline
1128 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1129 _ForwardIterator1
1130 find_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1131 _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
1132 {
1133 return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __pred);
1134 }
1135
1136 template <class _ForwardIterator1, class _ForwardIterator2>
1137 _LIBCPP_NODISCARD_EXT inline
1138 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1139 _ForwardIterator1
1140 find_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1141 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
1142 {
1143 typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
1144 typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1145 return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
1146 }
1147
1148 // adjacent_find
1149
1150 template <class _ForwardIterator, class _BinaryPredicate>
1151 _LIBCPP_NODISCARD_EXT inline
1152 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1153 _ForwardIterator
1154 adjacent_find(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
1155 {
1156 if (__first != __last)
1157 {
1158 _ForwardIterator __i = __first;
1159 while (++__i != __last)
1160 {
1161 if (__pred(*__first, *__i))
1162 return __first;
1163 __first = __i;
1164 }
1165 }
1166 return __last;
1167 }
1168
1169 template <class _ForwardIterator>
1170 _LIBCPP_NODISCARD_EXT inline
1171 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1172 _ForwardIterator
1173 adjacent_find(_ForwardIterator __first, _ForwardIterator __last)
1174 {
1175 typedef typename iterator_traits<_ForwardIterator>::value_type __v;
1176 return _VSTD::adjacent_find(__first, __last, __equal_to<__v>());
1177 }
1178
1179 // count
1180
1181 template <class _InputIterator, class _Tp>
1182 _LIBCPP_NODISCARD_EXT inline
1183 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1184 typename iterator_traits<_InputIterator>::difference_type
1185 count(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
1186 {
1187 typename iterator_traits<_InputIterator>::difference_type __r(0);
1188 for (; __first != __last; ++__first)
1189 if (*__first == __value_)
1190 ++__r;
1191 return __r;
1192 }
1193
1194 // count_if
1195
1196 template <class _InputIterator, class _Predicate>
1197 _LIBCPP_NODISCARD_EXT inline
1198 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1199 typename iterator_traits<_InputIterator>::difference_type
1200 count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
1201 {
1202 typename iterator_traits<_InputIterator>::difference_type __r(0);
1203 for (; __first != __last; ++__first)
1204 if (__pred(*__first))
1205 ++__r;
1206 return __r;
1207 }
1208
1209 // mismatch
1210
1211 template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
1212 _LIBCPP_NODISCARD_EXT inline
1213 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1214 pair<_InputIterator1, _InputIterator2>
1215 mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1216 _InputIterator2 __first2, _BinaryPredicate __pred)
1217 {
1218 for (; __first1 != __last1; ++__first1, (void) ++__first2)
1219 if (!__pred(*__first1, *__first2))
1220 break;
1221 return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
1222 }
1223
1224 template <class _InputIterator1, class _InputIterator2>
1225 _LIBCPP_NODISCARD_EXT inline
1226 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1227 pair<_InputIterator1, _InputIterator2>
1228 mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
1229 {
1230 typedef typename iterator_traits<_InputIterator1>::value_type __v1;
1231 typedef typename iterator_traits<_InputIterator2>::value_type __v2;
1232 return _VSTD::mismatch(__first1, __last1, __first2, __equal_to<__v1, __v2>());
1233 }
1234
1235 #if _LIBCPP_STD_VER > 11
1236 template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
1237 _LIBCPP_NODISCARD_EXT inline
1238 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1239 pair<_InputIterator1, _InputIterator2>
1240 mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1241 _InputIterator2 __first2, _InputIterator2 __last2,
1242 _BinaryPredicate __pred)
1243 {
1244 for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
1245 if (!__pred(*__first1, *__first2))
1246 break;
1247 return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
1248 }
1249
1250 template <class _InputIterator1, class _InputIterator2>
1251 _LIBCPP_NODISCARD_EXT inline
1252 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1253 pair<_InputIterator1, _InputIterator2>
1254 mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1255 _InputIterator2 __first2, _InputIterator2 __last2)
1256 {
1257 typedef typename iterator_traits<_InputIterator1>::value_type __v1;
1258 typedef typename iterator_traits<_InputIterator2>::value_type __v2;
1259 return _VSTD::mismatch(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
1260 }
1261 #endif
1262
1263 // equal
1264
1265 template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
1266 _LIBCPP_NODISCARD_EXT inline
1267 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1268 bool
1269 equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred)
1270 {
1271 for (; __first1 != __last1; ++__first1, (void) ++__first2)
1272 if (!__pred(*__first1, *__first2))
1273 return false;
1274 return true;
1275 }
1276
1277 template <class _InputIterator1, class _InputIterator2>
1278 _LIBCPP_NODISCARD_EXT inline
1279 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1280 bool
1281 equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
1282 {
1283 typedef typename iterator_traits<_InputIterator1>::value_type __v1;
1284 typedef typename iterator_traits<_InputIterator2>::value_type __v2;
1285 return _VSTD::equal(__first1, __last1, __first2, __equal_to<__v1, __v2>());
1286 }
1287
1288 #if _LIBCPP_STD_VER > 11
1289 template <class _BinaryPredicate, class _InputIterator1, class _InputIterator2>
1290 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1291 bool
1292 __equal(_InputIterator1 __first1, _InputIterator1 __last1,
1293 _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred,
1294 input_iterator_tag, input_iterator_tag )
1295 {
1296 for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
1297 if (!__pred(*__first1, *__first2))
1298 return false;
1299 return __first1 == __last1 && __first2 == __last2;
1300 }
1301
1302 template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
1303 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1304 bool
1305 __equal(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
1306 _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
1307 random_access_iterator_tag, random_access_iterator_tag )
1308 {
1309 if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
1310 return false;
1311 return _VSTD::equal<_RandomAccessIterator1, _RandomAccessIterator2,
1312 typename add_lvalue_reference<_BinaryPredicate>::type>
1313 (__first1, __last1, __first2, __pred );
1314 }
1315
1316 template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
1317 _LIBCPP_NODISCARD_EXT inline
1318 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1319 bool
1320 equal(_InputIterator1 __first1, _InputIterator1 __last1,
1321 _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred )
1322 {
1323 return _VSTD::__equal<typename add_lvalue_reference<_BinaryPredicate>::type>
1324 (__first1, __last1, __first2, __last2, __pred,
1325 typename iterator_traits<_InputIterator1>::iterator_category(),
1326 typename iterator_traits<_InputIterator2>::iterator_category());
1327 }
1328
1329 template <class _InputIterator1, class _InputIterator2>
1330 _LIBCPP_NODISCARD_EXT inline
1331 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1332 bool
1333 equal(_InputIterator1 __first1, _InputIterator1 __last1,
1334 _InputIterator2 __first2, _InputIterator2 __last2)
1335 {
1336 typedef typename iterator_traits<_InputIterator1>::value_type __v1;
1337 typedef typename iterator_traits<_InputIterator2>::value_type __v2;
1338 return _VSTD::__equal(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>(),
1339 typename iterator_traits<_InputIterator1>::iterator_category(),
1340 typename iterator_traits<_InputIterator2>::iterator_category());
1341 }
1342 #endif
1343
1344 // is_permutation
1345
1346 template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
1347 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
1348 is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1349 _ForwardIterator2 __first2, _BinaryPredicate __pred)
1350 {
1351 // shorten sequences as much as possible by lopping of any equal prefix
1352 for (; __first1 != __last1; ++__first1, (void) ++__first2)
1353 if (!__pred(*__first1, *__first2))
1354 break;
1355 if (__first1 == __last1)
1356 return true;
1357
1358 // __first1 != __last1 && *__first1 != *__first2
1359 typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
1360 _D1 __l1 = _VSTD::distance(__first1, __last1);
1361 if (__l1 == _D1(1))
1362 return false;
1363 _ForwardIterator2 __last2 = _VSTD::next(__first2, __l1);
1364 // For each element in [f1, l1) see if there are the same number of
1365 // equal elements in [f2, l2)
1366 for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
1367 {
1368 // Have we already counted the number of *__i in [f1, l1)?
1369 _ForwardIterator1 __match = __first1;
1370 for (; __match != __i; ++__match)
1371 if (__pred(*__match, *__i))
1372 break;
1373 if (__match == __i) {
1374 // Count number of *__i in [f2, l2)
1375 _D1 __c2 = 0;
1376 for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
1377 if (__pred(*__i, *__j))
1378 ++__c2;
1379 if (__c2 == 0)
1380 return false;
1381 // Count number of *__i in [__i, l1) (we can start with 1)
1382 _D1 __c1 = 1;
1383 for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
1384 if (__pred(*__i, *__j))
1385 ++__c1;
1386 if (__c1 != __c2)
1387 return false;
1388 }
1389 }
1390 return true;
1391 }
1392
1393 template<class _ForwardIterator1, class _ForwardIterator2>
1394 _LIBCPP_NODISCARD_EXT inline
1395 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1396 bool
1397 is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1398 _ForwardIterator2 __first2)
1399 {
1400 typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
1401 typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1402 return _VSTD::is_permutation(__first1, __last1, __first2, __equal_to<__v1, __v2>());
1403 }
1404
1405 #if _LIBCPP_STD_VER > 11
1406 template<class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
1407 _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
1408 __is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1409 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
1410 _BinaryPredicate __pred,
1411 forward_iterator_tag, forward_iterator_tag )
1412 {
1413 // shorten sequences as much as possible by lopping of any equal prefix
1414 for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
1415 if (!__pred(*__first1, *__first2))
1416 break;
1417 if (__first1 == __last1)
1418 return __first2 == __last2;
1419 else if (__first2 == __last2)
1420 return false;
1421
1422 typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
1423 _D1 __l1 = _VSTD::distance(__first1, __last1);
1424
1425 typedef typename iterator_traits<_ForwardIterator2>::difference_type _D2;
1426 _D2 __l2 = _VSTD::distance(__first2, __last2);
1427 if (__l1 != __l2)
1428 return false;
1429
1430 // For each element in [f1, l1) see if there are the same number of
1431 // equal elements in [f2, l2)
1432 for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
1433 {
1434 // Have we already counted the number of *__i in [f1, l1)?
1435 _ForwardIterator1 __match = __first1;
1436 for (; __match != __i; ++__match)
1437 if (__pred(*__match, *__i))
1438 break;
1439 if (__match == __i) {
1440 // Count number of *__i in [f2, l2)
1441 _D1 __c2 = 0;
1442 for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
1443 if (__pred(*__i, *__j))
1444 ++__c2;
1445 if (__c2 == 0)
1446 return false;
1447 // Count number of *__i in [__i, l1) (we can start with 1)
1448 _D1 __c1 = 1;
1449 for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
1450 if (__pred(*__i, *__j))
1451 ++__c1;
1452 if (__c1 != __c2)
1453 return false;
1454 }
1455 }
1456 return true;
1457 }
1458
1459 template<class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
1460 _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
1461 __is_permutation(_RandomAccessIterator1 __first1, _RandomAccessIterator2 __last1,
1462 _RandomAccessIterator1 __first2, _RandomAccessIterator2 __last2,
1463 _BinaryPredicate __pred,
1464 random_access_iterator_tag, random_access_iterator_tag )
1465 {
1466 if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
1467 return false;
1468 return _VSTD::is_permutation<_RandomAccessIterator1, _RandomAccessIterator2,
1469 typename add_lvalue_reference<_BinaryPredicate>::type>
1470 (__first1, __last1, __first2, __pred );
1471 }
1472
1473 template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
1474 _LIBCPP_NODISCARD_EXT inline
1475 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1476 bool
1477 is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1478 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
1479 _BinaryPredicate __pred )
1480 {
1481 return _VSTD::__is_permutation<typename add_lvalue_reference<_BinaryPredicate>::type>
1482 (__first1, __last1, __first2, __last2, __pred,
1483 typename iterator_traits<_ForwardIterator1>::iterator_category(),
1484 typename iterator_traits<_ForwardIterator2>::iterator_category());
1485 }
1486
1487 template<class _ForwardIterator1, class _ForwardIterator2>
1488 _LIBCPP_NODISCARD_EXT inline
1489 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1490 bool
1491 is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1492 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
1493 {
1494 typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
1495 typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1496 return _VSTD::__is_permutation(__first1, __last1, __first2, __last2,
1497 __equal_to<__v1, __v2>(),
1498 typename iterator_traits<_ForwardIterator1>::iterator_category(),
1499 typename iterator_traits<_ForwardIterator2>::iterator_category());
1500 }
1501 #endif
1502
1503 // search
1504 // __search is in <functional>
1505
1506 template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
1507 _LIBCPP_NODISCARD_EXT inline
1508 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1509 _ForwardIterator1
1510 search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1511 _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
1512 {
1513 return _VSTD::__search<typename add_lvalue_reference<_BinaryPredicate>::type>
1514 (__first1, __last1, __first2, __last2, __pred,
1515 typename iterator_traits<_ForwardIterator1>::iterator_category(),
1516 typename iterator_traits<_ForwardIterator2>::iterator_category())
1517 .first;
1518 }
1519
1520 template <class _ForwardIterator1, class _ForwardIterator2>
1521 _LIBCPP_NODISCARD_EXT inline
1522 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1523 _ForwardIterator1
1524 search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
1525 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
1526 {
1527 typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
1528 typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1529 return _VSTD::search(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
1530 }
1531
1532
1533 #if _LIBCPP_STD_VER > 14
1534 template <class _ForwardIterator, class _Searcher>
1535 _LIBCPP_NODISCARD_EXT _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1536 _ForwardIterator search(_ForwardIterator __f, _ForwardIterator __l, const _Searcher &__s)
1537 { return __s(__f, __l).first; }
1538 #endif
1539
1540 // search_n
1541
1542 template <class _BinaryPredicate, class _ForwardIterator, class _Size, class _Tp>
1543 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
1544 __search_n(_ForwardIterator __first, _ForwardIterator __last,
1545 _Size __count, const _Tp& __value_, _BinaryPredicate __pred, forward_iterator_tag)
1546 {
1547 if (__count <= 0)
1548 return __first;
1549 while (true)
1550 {
1551 // Find first element in sequence that matchs __value_, with a mininum of loop checks
1552 while (true)
1553 {
1554 if (__first == __last) // return __last if no element matches __value_
1555 return __last;
1556 if (__pred(*__first, __value_))
1557 break;
1558 ++__first;
1559 }
1560 // *__first matches __value_, now match elements after here
1561 _ForwardIterator __m = __first;
1562 _Size __c(0);
1563 while (true)
1564 {
1565 if (++__c == __count) // If pattern exhausted, __first is the answer (works for 1 element pattern)
1566 return __first;
1567 if (++__m == __last) // Otherwise if source exhaused, pattern not found
1568 return __last;
1569 if (!__pred(*__m, __value_)) // if there is a mismatch, restart with a new __first
1570 {
1571 __first = __m;
1572 ++__first;
1573 break;
1574 } // else there is a match, check next elements
1575 }
1576 }
1577 }
1578
1579 template <class _BinaryPredicate, class _RandomAccessIterator, class _Size, class _Tp>
1580 _LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
1581 __search_n(_RandomAccessIterator __first, _RandomAccessIterator __last,
1582 _Size __count, const _Tp& __value_, _BinaryPredicate __pred, random_access_iterator_tag)
1583 {
1584 if (__count <= 0)
1585 return __first;
1586 _Size __len = static_cast<_Size>(__last - __first);
1587 if (__len < __count)
1588 return __last;
1589 const _RandomAccessIterator __s = __last - (__count - 1); // Start of pattern match can't go beyond here
1590 while (true)
1591 {
1592 // Find first element in sequence that matchs __value_, with a mininum of loop checks
1593 while (true)
1594 {
1595 if (__first >= __s) // return __last if no element matches __value_
1596 return __last;
1597 if (__pred(*__first, __value_))
1598 break;
1599 ++__first;
1600 }
1601 // *__first matches __value_, now match elements after here
1602 _RandomAccessIterator __m = __first;
1603 _Size __c(0);
1604 while (true)
1605 {
1606 if (++__c == __count) // If pattern exhausted, __first is the answer (works for 1 element pattern)
1607 return __first;
1608 ++__m; // no need to check range on __m because __s guarantees we have enough source
1609 if (!__pred(*__m, __value_)) // if there is a mismatch, restart with a new __first
1610 {
1611 __first = __m;
1612 ++__first;
1613 break;
1614 } // else there is a match, check next elements
1615 }
1616 }
1617 }
1618
1619 template <class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate>
1620 _LIBCPP_NODISCARD_EXT inline
1621 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1622 _ForwardIterator
1623 search_n(_ForwardIterator __first, _ForwardIterator __last,
1624 _Size __count, const _Tp& __value_, _BinaryPredicate __pred)
1625 {
1626 return _VSTD::__search_n<typename add_lvalue_reference<_BinaryPredicate>::type>
1627 (__first, __last, _VSTD::__convert_to_integral(__count), __value_, __pred,
1628 typename iterator_traits<_ForwardIterator>::iterator_category());
1629 }
1630
1631 template <class _ForwardIterator, class _Size, class _Tp>
1632 _LIBCPP_NODISCARD_EXT inline
1633 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1634 _ForwardIterator
1635 search_n(_ForwardIterator __first, _ForwardIterator __last, _Size __count, const _Tp& __value_)
1636 {
1637 typedef typename iterator_traits<_ForwardIterator>::value_type __v;
1638 return _VSTD::search_n(__first, __last, _VSTD::__convert_to_integral(__count),
1639 __value_, __equal_to<__v, _Tp>());
1640 }
1641
1642 // __unwrap_iter, __rewrap_iter
1643
1644 // The job of __unwrap_iter is to lower contiguous iterators (such as
1645 // vector<T>::iterator) into pointers, to reduce the number of template
1646 // instantiations and to enable pointer-based optimizations e.g. in std::copy.
1647 // For iterators that are not contiguous, it must be a no-op.
1648 // In debug mode, we don't do this.
1649 //
1650 // __unwrap_iter is non-constexpr for user-defined iterators whose
1651 // `to_address` and/or `operator->` is non-constexpr. This is okay; but we
1652 // try to avoid doing __unwrap_iter in constant-evaluated contexts anyway.
1653 //
1654 // Some algorithms (e.g. std::copy, but not std::sort) need to convert an
1655 // "unwrapped" result back into a contiguous iterator. Since contiguous iterators
1656 // are random-access, we can do this portably using iterator arithmetic; this
1657 // is the job of __rewrap_iter.
1658
1659 template <class _Iter, bool = __is_cpp17_contiguous_iterator<_Iter>::value>
1660 struct __unwrap_iter_impl {
1661 static _LIBCPP_CONSTEXPR _Iter
1662 __apply(_Iter __i) _NOEXCEPT {
1663 return __i;
1664 }
1665 };
1666
1667 #if _LIBCPP_DEBUG_LEVEL < 2
1668
1669 template <class _Iter>
1670 struct __unwrap_iter_impl<_Iter, true> {
1671 static _LIBCPP_CONSTEXPR decltype(_VSTD::__to_address(declval<_Iter>()))
1672 __apply(_Iter __i) _NOEXCEPT {
1673 return _VSTD::__to_address(__i);
1674 }
1675 };
1676
1677 #endif // _LIBCPP_DEBUG_LEVEL < 2
1678
1679 template<class _Iter, class _Impl = __unwrap_iter_impl<_Iter> >
1680 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1681 decltype(_Impl::__apply(declval<_Iter>()))
1682 __unwrap_iter(_Iter __i) _NOEXCEPT
1683 {
1684 return _Impl::__apply(__i);
1685 }
1686
1687 template<class _OrigIter>
1688 _OrigIter __rewrap_iter(_OrigIter, _OrigIter __result)
1689 {
1690 return __result;
1691 }
1692
1693 template<class _OrigIter, class _UnwrappedIter>
1694 _OrigIter __rewrap_iter(_OrigIter __first, _UnwrappedIter __result)
1695 {
1696 // Precondition: __result is reachable from __first
1697 // Precondition: _OrigIter is a contiguous iterator
1698 return __first + (__result - _VSTD::__unwrap_iter(__first));
1699 }
1700
1701 // copy
1702
1703 template <class _InputIterator, class _OutputIterator>
1704 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1705 _OutputIterator
1706 __copy_constexpr(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
1707 {
1708 for (; __first != __last; ++__first, (void) ++__result)
1709 *__result = *__first;
1710 return __result;
1711 }
1712
1713 template <class _InputIterator, class _OutputIterator>
1714 inline _LIBCPP_INLINE_VISIBILITY
1715 _OutputIterator
1716 __copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
1717 {
1718 return _VSTD::__copy_constexpr(__first, __last, __result);
1719 }
1720
1721 template <class _Tp, class _Up>
1722 inline _LIBCPP_INLINE_VISIBILITY
1723 typename enable_if
1724 <
1725 is_same<typename remove_const<_Tp>::type, _Up>::value &&
1726 is_trivially_copy_assignable<_Up>::value,
1727 _Up*
1728 >::type
1729 __copy(_Tp* __first, _Tp* __last, _Up* __result)
1730 {
1731 const size_t __n = static_cast<size_t>(__last - __first);
1732 if (__n > 0)
1733 _VSTD::memmove(__result, __first, __n * sizeof(_Up));
1734 return __result + __n;
1735 }
1736
1737 template <class _InputIterator, class _OutputIterator>
1738 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1739 _OutputIterator
1740 copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
1741 {
1742 if (__libcpp_is_constant_evaluated()) {
1743 return _VSTD::__copy_constexpr(__first, __last, __result);
1744 } else {
1745 return _VSTD::__rewrap_iter(__result,
1746 _VSTD::__copy(_VSTD::__unwrap_iter(__first),
1747 _VSTD::__unwrap_iter(__last),
1748 _VSTD::__unwrap_iter(__result)));
1749 }
1750 }
1751
1752 // copy_backward
1753
1754 template <class _BidirectionalIterator, class _OutputIterator>
1755 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1756 _OutputIterator
1757 __copy_backward_constexpr(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
1758 {
1759 while (__first != __last)
1760 *--__result = *--__last;
1761 return __result;
1762 }
1763
1764 template <class _BidirectionalIterator, class _OutputIterator>
1765 inline _LIBCPP_INLINE_VISIBILITY
1766 _OutputIterator
1767 __copy_backward(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
1768 {
1769 return _VSTD::__copy_backward_constexpr(__first, __last, __result);
1770 }
1771
1772 template <class _Tp, class _Up>
1773 inline _LIBCPP_INLINE_VISIBILITY
1774 typename enable_if
1775 <
1776 is_same<typename remove_const<_Tp>::type, _Up>::value &&
1777 is_trivially_copy_assignable<_Up>::value,
1778 _Up*
1779 >::type
1780 __copy_backward(_Tp* __first, _Tp* __last, _Up* __result)
1781 {
1782 const size_t __n = static_cast<size_t>(__last - __first);
1783 if (__n > 0)
1784 {
1785 __result -= __n;
1786 _VSTD::memmove(__result, __first, __n * sizeof(_Up));
1787 }
1788 return __result;
1789 }
1790
1791 template <class _BidirectionalIterator1, class _BidirectionalIterator2>
1792 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1793 _BidirectionalIterator2
1794 copy_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
1795 _BidirectionalIterator2 __result)
1796 {
1797 if (__libcpp_is_constant_evaluated()) {
1798 return _VSTD::__copy_backward_constexpr(__first, __last, __result);
1799 } else {
1800 return _VSTD::__rewrap_iter(__result,
1801 _VSTD::__copy_backward(_VSTD::__unwrap_iter(__first),
1802 _VSTD::__unwrap_iter(__last),
1803 _VSTD::__unwrap_iter(__result)));
1804 }
1805 }
1806
1807 // copy_if
1808
1809 template<class _InputIterator, class _OutputIterator, class _Predicate>
1810 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1811 _OutputIterator
1812 copy_if(_InputIterator __first, _InputIterator __last,
1813 _OutputIterator __result, _Predicate __pred)
1814 {
1815 for (; __first != __last; ++__first)
1816 {
1817 if (__pred(*__first))
1818 {
1819 *__result = *__first;
1820 ++__result;
1821 }
1822 }
1823 return __result;
1824 }
1825
1826 // copy_n
1827
1828 template<class _InputIterator, class _Size, class _OutputIterator>
1829 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1830 typename enable_if
1831 <
1832 __is_cpp17_input_iterator<_InputIterator>::value &&
1833 !__is_cpp17_random_access_iterator<_InputIterator>::value,
1834 _OutputIterator
1835 >::type
1836 copy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
1837 {
1838 typedef decltype(_VSTD::__convert_to_integral(__orig_n)) _IntegralSize;
1839 _IntegralSize __n = __orig_n;
1840 if (__n > 0)
1841 {
1842 *__result = *__first;
1843 ++__result;
1844 for (--__n; __n > 0; --__n)
1845 {
1846 ++__first;
1847 *__result = *__first;
1848 ++__result;
1849 }
1850 }
1851 return __result;
1852 }
1853
1854 template<class _InputIterator, class _Size, class _OutputIterator>
1855 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1856 typename enable_if
1857 <
1858 __is_cpp17_random_access_iterator<_InputIterator>::value,
1859 _OutputIterator
1860 >::type
1861 copy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
1862 {
1863 typedef decltype(_VSTD::__convert_to_integral(__orig_n)) _IntegralSize;
1864 _IntegralSize __n = __orig_n;
1865 return _VSTD::copy(__first, __first + __n, __result);
1866 }
1867
1868 // move
1869
1870 template <class _InputIterator, class _OutputIterator>
1871 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1872 _OutputIterator
1873 __move_constexpr(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
1874 {
1875 for (; __first != __last; ++__first, (void) ++__result)
1876 *__result = _VSTD::move(*__first);
1877 return __result;
1878 }
1879
1880 template <class _InputIterator, class _OutputIterator>
1881 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1882 _OutputIterator
1883 __move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
1884 {
1885 return _VSTD::__move_constexpr(__first, __last, __result);
1886 }
1887
1888 template <class _Tp, class _Up>
1889 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1890 typename enable_if
1891 <
1892 is_same<typename remove_const<_Tp>::type, _Up>::value &&
1893 is_trivially_move_assignable<_Up>::value,
1894 _Up*
1895 >::type
1896 __move(_Tp* __first, _Tp* __last, _Up* __result)
1897 {
1898 const size_t __n = static_cast<size_t>(__last - __first);
1899 if (__n > 0)
1900 _VSTD::memmove(__result, __first, __n * sizeof(_Up));
1901 return __result + __n;
1902 }
1903
1904 template <class _InputIterator, class _OutputIterator>
1905 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1906 _OutputIterator
1907 move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
1908 {
1909 if (__libcpp_is_constant_evaluated()) {
1910 return _VSTD::__move_constexpr(__first, __last, __result);
1911 } else {
1912 return _VSTD::__rewrap_iter(__result,
1913 _VSTD::__move(_VSTD::__unwrap_iter(__first),
1914 _VSTD::__unwrap_iter(__last),
1915 _VSTD::__unwrap_iter(__result)));
1916 }
1917 }
1918
1919 // move_backward
1920
1921 template <class _InputIterator, class _OutputIterator>
1922 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1923 _OutputIterator
1924 __move_backward_constexpr(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
1925 {
1926 while (__first != __last)
1927 *--__result = _VSTD::move(*--__last);
1928 return __result;
1929 }
1930
1931 template <class _InputIterator, class _OutputIterator>
1932 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1933 _OutputIterator
1934 __move_backward(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
1935 {
1936 return _VSTD::__move_backward_constexpr(__first, __last, __result);
1937 }
1938
1939 template <class _Tp, class _Up>
1940 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1941 typename enable_if
1942 <
1943 is_same<typename remove_const<_Tp>::type, _Up>::value &&
1944 is_trivially_move_assignable<_Up>::value,
1945 _Up*
1946 >::type
1947 __move_backward(_Tp* __first, _Tp* __last, _Up* __result)
1948 {
1949 const size_t __n = static_cast<size_t>(__last - __first);
1950 if (__n > 0)
1951 {
1952 __result -= __n;
1953 _VSTD::memmove(__result, __first, __n * sizeof(_Up));
1954 }
1955 return __result;
1956 }
1957
1958 template <class _BidirectionalIterator1, class _BidirectionalIterator2>
1959 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1960 _BidirectionalIterator2
1961 move_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
1962 _BidirectionalIterator2 __result)
1963 {
1964 if (__libcpp_is_constant_evaluated()) {
1965 return _VSTD::__move_backward_constexpr(__first, __last, __result);
1966 } else {
1967 return _VSTD::__rewrap_iter(__result,
1968 _VSTD::__move_backward(_VSTD::__unwrap_iter(__first),
1969 _VSTD::__unwrap_iter(__last),
1970 _VSTD::__unwrap_iter(__result)));
1971 }
1972 }
1973
1974 // iter_swap
1975
1976 // moved to <type_traits> for better swap / noexcept support
1977
1978 // transform
1979
1980 template <class _InputIterator, class _OutputIterator, class _UnaryOperation>
1981 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1982 _OutputIterator
1983 transform(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _UnaryOperation __op)
1984 {
1985 for (; __first != __last; ++__first, (void) ++__result)
1986 *__result = __op(*__first);
1987 return __result;
1988 }
1989
1990 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _BinaryOperation>
1991 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1992 _OutputIterator
1993 transform(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2,
1994 _OutputIterator __result, _BinaryOperation __binary_op)
1995 {
1996 for (; __first1 != __last1; ++__first1, (void) ++__first2, ++__result)
1997 *__result = __binary_op(*__first1, *__first2);
1998 return __result;
1999 }
2000
2001 // replace
2002
2003 template <class _ForwardIterator, class _Tp>
2004 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2005 void
2006 replace(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __old_value, const _Tp& __new_value)
2007 {
2008 for (; __first != __last; ++__first)
2009 if (*__first == __old_value)
2010 *__first = __new_value;
2011 }
2012
2013 // replace_if
2014
2015 template <class _ForwardIterator, class _Predicate, class _Tp>
2016 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2017 void
2018 replace_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, const _Tp& __new_value)
2019 {
2020 for (; __first != __last; ++__first)
2021 if (__pred(*__first))
2022 *__first = __new_value;
2023 }
2024
2025 // replace_copy
2026
2027 template <class _InputIterator, class _OutputIterator, class _Tp>
2028 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2029 _OutputIterator
2030 replace_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
2031 const _Tp& __old_value, const _Tp& __new_value)
2032 {
2033 for (; __first != __last; ++__first, (void) ++__result)
2034 if (*__first == __old_value)
2035 *__result = __new_value;
2036 else
2037 *__result = *__first;
2038 return __result;
2039 }
2040
2041 // replace_copy_if
2042
2043 template <class _InputIterator, class _OutputIterator, class _Predicate, class _Tp>
2044 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2045 _OutputIterator
2046 replace_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
2047 _Predicate __pred, const _Tp& __new_value)
2048 {
2049 for (; __first != __last; ++__first, (void) ++__result)
2050 if (__pred(*__first))
2051 *__result = __new_value;
2052 else
2053 *__result = *__first;
2054 return __result;
2055 }
2056
2057 // fill_n
2058
2059 template <class _OutputIterator, class _Size, class _Tp>
2060 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2061 _OutputIterator
2062 __fill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
2063 {
2064 for (; __n > 0; ++__first, (void) --__n)
2065 *__first = __value_;
2066 return __first;
2067 }
2068
2069 template <class _OutputIterator, class _Size, class _Tp>
2070 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2071 _OutputIterator
2072 fill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
2073 {
2074 return _VSTD::__fill_n(__first, _VSTD::__convert_to_integral(__n), __value_);
2075 }
2076
2077 // fill
2078
2079 template <class _ForwardIterator, class _Tp>
2080 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2081 void
2082 __fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, forward_iterator_tag)
2083 {
2084 for (; __first != __last; ++__first)
2085 *__first = __value_;
2086 }
2087
2088 template <class _RandomAccessIterator, class _Tp>
2089 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2090 void
2091 __fill(_RandomAccessIterator __first, _RandomAccessIterator __last, const _Tp& __value_, random_access_iterator_tag)
2092 {
2093 _VSTD::fill_n(__first, __last - __first, __value_);
2094 }
2095
2096 template <class _ForwardIterator, class _Tp>
2097 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2098 void
2099 fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
2100 {
2101 _VSTD::__fill(__first, __last, __value_, typename iterator_traits<_ForwardIterator>::iterator_category());
2102 }
2103
2104 // generate
2105
2106 template <class _ForwardIterator, class _Generator>
2107 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2108 void
2109 generate(_ForwardIterator __first, _ForwardIterator __last, _Generator __gen)
2110 {
2111 for (; __first != __last; ++__first)
2112 *__first = __gen();
2113 }
2114
2115 // generate_n
2116
2117 template <class _OutputIterator, class _Size, class _Generator>
2118 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2119 _OutputIterator
2120 generate_n(_OutputIterator __first, _Size __orig_n, _Generator __gen)
2121 {
2122 typedef decltype(_VSTD::__convert_to_integral(__orig_n)) _IntegralSize;
2123 _IntegralSize __n = __orig_n;
2124 for (; __n > 0; ++__first, (void) --__n)
2125 *__first = __gen();
2126 return __first;
2127 }
2128
2129 // remove
2130
2131 template <class _ForwardIterator, class _Tp>
2132 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
2133 remove(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
2134 {
2135 __first = _VSTD::find(__first, __last, __value_);
2136 if (__first != __last)
2137 {
2138 _ForwardIterator __i = __first;
2139 while (++__i != __last)
2140 {
2141 if (!(*__i == __value_))
2142 {
2143 *__first = _VSTD::move(*__i);
2144 ++__first;
2145 }
2146 }
2147 }
2148 return __first;
2149 }
2150
2151 // remove_if
2152
2153 template <class _ForwardIterator, class _Predicate>
2154 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
2155 remove_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
2156 {
2157 __first = _VSTD::find_if<_ForwardIterator, typename add_lvalue_reference<_Predicate>::type>
2158 (__first, __last, __pred);
2159 if (__first != __last)
2160 {
2161 _ForwardIterator __i = __first;
2162 while (++__i != __last)
2163 {
2164 if (!__pred(*__i))
2165 {
2166 *__first = _VSTD::move(*__i);
2167 ++__first;
2168 }
2169 }
2170 }
2171 return __first;
2172 }
2173
2174 // remove_copy
2175
2176 template <class _InputIterator, class _OutputIterator, class _Tp>
2177 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2178 _OutputIterator
2179 remove_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, const _Tp& __value_)
2180 {
2181 for (; __first != __last; ++__first)
2182 {
2183 if (!(*__first == __value_))
2184 {
2185 *__result = *__first;
2186 ++__result;
2187 }
2188 }
2189 return __result;
2190 }
2191
2192 // remove_copy_if
2193
2194 template <class _InputIterator, class _OutputIterator, class _Predicate>
2195 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2196 _OutputIterator
2197 remove_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Predicate __pred)
2198 {
2199 for (; __first != __last; ++__first)
2200 {
2201 if (!__pred(*__first))
2202 {
2203 *__result = *__first;
2204 ++__result;
2205 }
2206 }
2207 return __result;
2208 }
2209
2210 // unique
2211
2212 template <class _ForwardIterator, class _BinaryPredicate>
2213 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
2214 unique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
2215 {
2216 __first = _VSTD::adjacent_find<_ForwardIterator, typename add_lvalue_reference<_BinaryPredicate>::type>
2217 (__first, __last, __pred);
2218 if (__first != __last)
2219 {
2220 // ... a a ? ...
2221 // f i
2222 _ForwardIterator __i = __first;
2223 for (++__i; ++__i != __last;)
2224 if (!__pred(*__first, *__i))
2225 *++__first = _VSTD::move(*__i);
2226 ++__first;
2227 }
2228 return __first;
2229 }
2230
2231 template <class _ForwardIterator>
2232 _LIBCPP_NODISCARD_EXT inline
2233 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2234 _ForwardIterator
2235 unique(_ForwardIterator __first, _ForwardIterator __last)
2236 {
2237 typedef typename iterator_traits<_ForwardIterator>::value_type __v;
2238 return _VSTD::unique(__first, __last, __equal_to<__v>());
2239 }
2240
2241 // unique_copy
2242
2243 template <class _BinaryPredicate, class _InputIterator, class _OutputIterator>
2244 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
2245 __unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
2246 input_iterator_tag, output_iterator_tag)
2247 {
2248 if (__first != __last)
2249 {
2250 typename iterator_traits<_InputIterator>::value_type __t(*__first);
2251 *__result = __t;
2252 ++__result;
2253 while (++__first != __last)
2254 {
2255 if (!__pred(__t, *__first))
2256 {
2257 __t = *__first;
2258 *__result = __t;
2259 ++__result;
2260 }
2261 }
2262 }
2263 return __result;
2264 }
2265
2266 template <class _BinaryPredicate, class _ForwardIterator, class _OutputIterator>
2267 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
2268 __unique_copy(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
2269 forward_iterator_tag, output_iterator_tag)
2270 {
2271 if (__first != __last)
2272 {
2273 _ForwardIterator __i = __first;
2274 *__result = *__i;
2275 ++__result;
2276 while (++__first != __last)
2277 {
2278 if (!__pred(*__i, *__first))
2279 {
2280 *__result = *__first;
2281 ++__result;
2282 __i = __first;
2283 }
2284 }
2285 }
2286 return __result;
2287 }
2288
2289 template <class _BinaryPredicate, class _InputIterator, class _ForwardIterator>
2290 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
2291 __unique_copy(_InputIterator __first, _InputIterator __last, _ForwardIterator __result, _BinaryPredicate __pred,
2292 input_iterator_tag, forward_iterator_tag)
2293 {
2294 if (__first != __last)
2295 {
2296 *__result = *__first;
2297 while (++__first != __last)
2298 if (!__pred(*__result, *__first))
2299 *++__result = *__first;
2300 ++__result;
2301 }
2302 return __result;
2303 }
2304
2305 template <class _InputIterator, class _OutputIterator, class _BinaryPredicate>
2306 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2307 _OutputIterator
2308 unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred)
2309 {
2310 return _VSTD::__unique_copy<typename add_lvalue_reference<_BinaryPredicate>::type>
2311 (__first, __last, __result, __pred,
2312 typename iterator_traits<_InputIterator>::iterator_category(),
2313 typename iterator_traits<_OutputIterator>::iterator_category());
2314 }
2315
2316 template <class _InputIterator, class _OutputIterator>
2317 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2318 _OutputIterator
2319 unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
2320 {
2321 typedef typename iterator_traits<_InputIterator>::value_type __v;
2322 return _VSTD::unique_copy(__first, __last, __result, __equal_to<__v>());
2323 }
2324
2325 // reverse
2326
2327 template <class _BidirectionalIterator>
2328 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2329 void
2330 __reverse(_BidirectionalIterator __first, _BidirectionalIterator __last, bidirectional_iterator_tag)
2331 {
2332 while (__first != __last)
2333 {
2334 if (__first == --__last)
2335 break;
2336 _VSTD::iter_swap(__first, __last);
2337 ++__first;
2338 }
2339 }
2340
2341 template <class _RandomAccessIterator>
2342 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2343 void
2344 __reverse(_RandomAccessIterator __first, _RandomAccessIterator __last, random_access_iterator_tag)
2345 {
2346 if (__first != __last)
2347 for (; __first < --__last; ++__first)
2348 _VSTD::iter_swap(__first, __last);
2349 }
2350
2351 template <class _BidirectionalIterator>
2352 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2353 void
2354 reverse(_BidirectionalIterator __first, _BidirectionalIterator __last)
2355 {
2356 _VSTD::__reverse(__first, __last, typename iterator_traits<_BidirectionalIterator>::iterator_category());
2357 }
2358
2359 // reverse_copy
2360
2361 template <class _BidirectionalIterator, class _OutputIterator>
2362 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2363 _OutputIterator
2364 reverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
2365 {
2366 for (; __first != __last; ++__result)
2367 *__result = *--__last;
2368 return __result;
2369 }
2370
2371 // rotate
2372
2373 template <class _ForwardIterator>
2374 _LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator
2375 __rotate_left(_ForwardIterator __first, _ForwardIterator __last)
2376 {
2377 typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
2378 value_type __tmp = _VSTD::move(*__first);
2379 _ForwardIterator __lm1 = _VSTD::move(_VSTD::next(__first), __last, __first);
2380 *__lm1 = _VSTD::move(__tmp);
2381 return __lm1;
2382 }
2383
2384 template <class _BidirectionalIterator>
2385 _LIBCPP_CONSTEXPR_AFTER_CXX11 _BidirectionalIterator
2386 __rotate_right(_BidirectionalIterator __first, _BidirectionalIterator __last)
2387 {
2388 typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
2389 _BidirectionalIterator __lm1 = _VSTD::prev(__last);
2390 value_type __tmp = _VSTD::move(*__lm1);
2391 _BidirectionalIterator __fp1 = _VSTD::move_backward(__first, __lm1, __last);
2392 *__first = _VSTD::move(__tmp);
2393 return __fp1;
2394 }
2395
2396 template <class _ForwardIterator>
2397 _LIBCPP_CONSTEXPR_AFTER_CXX14 _ForwardIterator
2398 __rotate_forward(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
2399 {
2400 _ForwardIterator __i = __middle;
2401 while (true)
2402 {
2403 swap(*__first, *__i);
2404 ++__first;
2405 if (++__i == __last)
2406 break;
2407 if (__first == __middle)
2408 __middle = __i;
2409 }
2410 _ForwardIterator __r = __first;
2411 if (__first != __middle)
2412 {
2413 __i = __middle;
2414 while (true)
2415 {
2416 swap(*__first, *__i);
2417 ++__first;
2418 if (++__i == __last)
2419 {
2420 if (__first == __middle)
2421 break;
2422 __i = __middle;
2423 }
2424 else if (__first == __middle)
2425 __middle = __i;
2426 }
2427 }
2428 return __r;
2429 }
2430
2431 template<typename _Integral>
2432 inline _LIBCPP_INLINE_VISIBILITY
2433 _LIBCPP_CONSTEXPR_AFTER_CXX14 _Integral
2434 __algo_gcd(_Integral __x, _Integral __y)
2435 {
2436 do
2437 {
2438 _Integral __t = __x % __y;
2439 __x = __y;
2440 __y = __t;
2441 } while (__y);
2442 return __x;
2443 }
2444
2445 template<typename _RandomAccessIterator>
2446 _LIBCPP_CONSTEXPR_AFTER_CXX14 _RandomAccessIterator
2447 __rotate_gcd(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
2448 {
2449 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
2450 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
2451
2452 const difference_type __m1 = __middle - __first;
2453 const difference_type __m2 = __last - __middle;
2454 if (__m1 == __m2)
2455 {
2456 _VSTD::swap_ranges(__first, __middle, __middle);
2457 return __middle;
2458 }
2459 const difference_type __g = _VSTD::__algo_gcd(__m1, __m2);
2460 for (_RandomAccessIterator __p = __first + __g; __p != __first;)
2461 {
2462 value_type __t(_VSTD::move(*--__p));
2463 _RandomAccessIterator __p1 = __p;
2464 _RandomAccessIterator __p2 = __p1 + __m1;
2465 do
2466 {
2467 *__p1 = _VSTD::move(*__p2);
2468 __p1 = __p2;
2469 const difference_type __d = __last - __p2;
2470 if (__m1 < __d)
2471 __p2 += __m1;
2472 else
2473 __p2 = __first + (__m1 - __d);
2474 } while (__p2 != __p);
2475 *__p1 = _VSTD::move(__t);
2476 }
2477 return __first + __m2;
2478 }
2479
2480 template <class _ForwardIterator>
2481 inline _LIBCPP_INLINE_VISIBILITY
2482 _LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator
2483 __rotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last,
2484 _VSTD::forward_iterator_tag)
2485 {
2486 typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
2487 if (is_trivially_move_assignable<value_type>::value)
2488 {
2489 if (_VSTD::next(__first) == __middle)
2490 return _VSTD::__rotate_left(__first, __last);
2491 }
2492 return _VSTD::__rotate_forward(__first, __middle, __last);
2493 }
2494
2495 template <class _BidirectionalIterator>
2496 inline _LIBCPP_INLINE_VISIBILITY
2497 _LIBCPP_CONSTEXPR_AFTER_CXX11 _BidirectionalIterator
2498 __rotate(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
2499 bidirectional_iterator_tag)
2500 {
2501 typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
2502 if (is_trivially_move_assignable<value_type>::value)
2503 {
2504 if (_VSTD::next(__first) == __middle)
2505 return _VSTD::__rotate_left(__first, __last);
2506 if (_VSTD::next(__middle) == __last)
2507 return _VSTD::__rotate_right(__first, __last);
2508 }
2509 return _VSTD::__rotate_forward(__first, __middle, __last);
2510 }
2511
2512 template <class _RandomAccessIterator>
2513 inline _LIBCPP_INLINE_VISIBILITY
2514 _LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator
2515 __rotate(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
2516 random_access_iterator_tag)
2517 {
2518 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
2519 if (is_trivially_move_assignable<value_type>::value)
2520 {
2521 if (_VSTD::next(__first) == __middle)
2522 return _VSTD::__rotate_left(__first, __last);
2523 if (_VSTD::next(__middle) == __last)
2524 return _VSTD::__rotate_right(__first, __last);
2525 return _VSTD::__rotate_gcd(__first, __middle, __last);
2526 }
2527 return _VSTD::__rotate_forward(__first, __middle, __last);
2528 }
2529
2530 template <class _ForwardIterator>
2531 inline _LIBCPP_INLINE_VISIBILITY
2532 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
2533 rotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
2534 {
2535 if (__first == __middle)
2536 return __last;
2537 if (__middle == __last)
2538 return __first;
2539 return _VSTD::__rotate(__first, __middle, __last,
2540 typename iterator_traits<_ForwardIterator>::iterator_category());
2541 }
2542
2543 // rotate_copy
2544
2545 template <class _ForwardIterator, class _OutputIterator>
2546 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2547 _OutputIterator
2548 rotate_copy(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last, _OutputIterator __result)
2549 {
2550 return _VSTD::copy(__first, __middle, _VSTD::copy(__middle, __last, __result));
2551 }
2552
2553 // min_element
2554
2555 template <class _ForwardIterator, class _Compare>
2556 _LIBCPP_NODISCARD_EXT inline
2557 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2558 _ForwardIterator
2559 min_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
2560 {
2561 static_assert(__is_cpp17_forward_iterator<_ForwardIterator>::value,
2562 "std::min_element requires a ForwardIterator");
2563 if (__first != __last)
2564 {
2565 _ForwardIterator __i = __first;
2566 while (++__i != __last)
2567 if (__comp(*__i, *__first))
2568 __first = __i;
2569 }
2570 return __first;
2571 }
2572
2573 template <class _ForwardIterator>
2574 _LIBCPP_NODISCARD_EXT inline
2575 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2576 _ForwardIterator
2577 min_element(_ForwardIterator __first, _ForwardIterator __last)
2578 {
2579 return _VSTD::min_element(__first, __last,
2580 __less<typename iterator_traits<_ForwardIterator>::value_type>());
2581 }
2582
2583 // min
2584
2585 template <class _Tp, class _Compare>
2586 _LIBCPP_NODISCARD_EXT inline
2587 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2588 const _Tp&
2589 min(const _Tp& __a, const _Tp& __b, _Compare __comp)
2590 {
2591 return __comp(__b, __a) ? __b : __a;
2592 }
2593
2594 template <class _Tp>
2595 _LIBCPP_NODISCARD_EXT inline
2596 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2597 const _Tp&
2598 min(const _Tp& __a, const _Tp& __b)
2599 {
2600 return _VSTD::min(__a, __b, __less<_Tp>());
2601 }
2602
2603 #ifndef _LIBCPP_CXX03_LANG
2604
2605 template<class _Tp, class _Compare>
2606 _LIBCPP_NODISCARD_EXT inline
2607 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2608 _Tp
2609 min(initializer_list<_Tp> __t, _Compare __comp)
2610 {
2611 return *_VSTD::min_element(__t.begin(), __t.end(), __comp);
2612 }
2613
2614 template<class _Tp>
2615 _LIBCPP_NODISCARD_EXT inline
2616 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2617 _Tp
2618 min(initializer_list<_Tp> __t)
2619 {
2620 return *_VSTD::min_element(__t.begin(), __t.end(), __less<_Tp>());
2621 }
2622
2623 #endif // _LIBCPP_CXX03_LANG
2624
2625 // max_element
2626
2627 template <class _ForwardIterator, class _Compare>
2628 _LIBCPP_NODISCARD_EXT inline
2629 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2630 _ForwardIterator
2631 max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
2632 {
2633 static_assert(__is_cpp17_forward_iterator<_ForwardIterator>::value,
2634 "std::max_element requires a ForwardIterator");
2635 if (__first != __last)
2636 {
2637 _ForwardIterator __i = __first;
2638 while (++__i != __last)
2639 if (__comp(*__first, *__i))
2640 __first = __i;
2641 }
2642 return __first;
2643 }
2644
2645
2646 template <class _ForwardIterator>
2647 _LIBCPP_NODISCARD_EXT inline
2648 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2649 _ForwardIterator
2650 max_element(_ForwardIterator __first, _ForwardIterator __last)
2651 {
2652 return _VSTD::max_element(__first, __last,
2653 __less<typename iterator_traits<_ForwardIterator>::value_type>());
2654 }
2655
2656 // max
2657
2658 template <class _Tp, class _Compare>
2659 _LIBCPP_NODISCARD_EXT inline
2660 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2661 const _Tp&
2662 max(const _Tp& __a, const _Tp& __b, _Compare __comp)
2663 {
2664 return __comp(__a, __b) ? __b : __a;
2665 }
2666
2667 template <class _Tp>
2668 _LIBCPP_NODISCARD_EXT inline
2669 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2670 const _Tp&
2671 max(const _Tp& __a, const _Tp& __b)
2672 {
2673 return _VSTD::max(__a, __b, __less<_Tp>());
2674 }
2675
2676 #ifndef _LIBCPP_CXX03_LANG
2677
2678 template<class _Tp, class _Compare>
2679 _LIBCPP_NODISCARD_EXT inline
2680 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2681 _Tp
2682 max(initializer_list<_Tp> __t, _Compare __comp)
2683 {
2684 return *_VSTD::max_element(__t.begin(), __t.end(), __comp);
2685 }
2686
2687 template<class _Tp>
2688 _LIBCPP_NODISCARD_EXT inline
2689 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2690 _Tp
2691 max(initializer_list<_Tp> __t)
2692 {
2693 return *_VSTD::max_element(__t.begin(), __t.end(), __less<_Tp>());
2694 }
2695
2696 #endif // _LIBCPP_CXX03_LANG
2697
2698 #if _LIBCPP_STD_VER > 14
2699 // clamp
2700 template<class _Tp, class _Compare>
2701 _LIBCPP_NODISCARD_EXT inline
2702 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2703 const _Tp&
2704 clamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi, _Compare __comp)
2705 {
2706 _LIBCPP_ASSERT(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
2707 return __comp(__v, __lo) ? __lo : __comp(__hi, __v) ? __hi : __v;
2708
2709 }
2710
2711 template<class _Tp>
2712 _LIBCPP_NODISCARD_EXT inline
2713 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2714 const _Tp&
2715 clamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi)
2716 {
2717 return _VSTD::clamp(__v, __lo, __hi, __less<_Tp>());
2718 }
2719 #endif
2720
2721 // minmax_element
2722
2723 template <class _ForwardIterator, class _Compare>
2724 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX11
2725 pair<_ForwardIterator, _ForwardIterator>
2726 minmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
2727 {
2728 static_assert(__is_cpp17_forward_iterator<_ForwardIterator>::value,
2729 "std::minmax_element requires a ForwardIterator");
2730 pair<_ForwardIterator, _ForwardIterator> __result(__first, __first);
2731 if (__first != __last)
2732 {
2733 if (++__first != __last)
2734 {
2735 if (__comp(*__first, *__result.first))
2736 __result.first = __first;
2737 else
2738 __result.second = __first;
2739 while (++__first != __last)
2740 {
2741 _ForwardIterator __i = __first;
2742 if (++__first == __last)
2743 {
2744 if (__comp(*__i, *__result.first))
2745 __result.first = __i;
2746 else if (!__comp(*__i, *__result.second))
2747 __result.second = __i;
2748 break;
2749 }
2750 else
2751 {
2752 if (__comp(*__first, *__i))
2753 {
2754 if (__comp(*__first, *__result.first))
2755 __result.first = __first;
2756 if (!__comp(*__i, *__result.second))
2757 __result.second = __i;
2758 }
2759 else
2760 {
2761 if (__comp(*__i, *__result.first))
2762 __result.first = __i;
2763 if (!__comp(*__first, *__result.second))
2764 __result.second = __first;
2765 }
2766 }
2767 }
2768 }
2769 }
2770 return __result;
2771 }
2772
2773 template <class _ForwardIterator>
2774 _LIBCPP_NODISCARD_EXT inline
2775 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2776 pair<_ForwardIterator, _ForwardIterator>
2777 minmax_element(_ForwardIterator __first, _ForwardIterator __last)
2778 {
2779 return _VSTD::minmax_element(__first, __last,
2780 __less<typename iterator_traits<_ForwardIterator>::value_type>());
2781 }
2782
2783 // minmax
2784
2785 template<class _Tp, class _Compare>
2786 _LIBCPP_NODISCARD_EXT inline
2787 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2788 pair<const _Tp&, const _Tp&>
2789 minmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
2790 {
2791 return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a) :
2792 pair<const _Tp&, const _Tp&>(__a, __b);
2793 }
2794
2795 template<class _Tp>
2796 _LIBCPP_NODISCARD_EXT inline
2797 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2798 pair<const _Tp&, const _Tp&>
2799 minmax(const _Tp& __a, const _Tp& __b)
2800 {
2801 return _VSTD::minmax(__a, __b, __less<_Tp>());
2802 }
2803
2804 #ifndef _LIBCPP_CXX03_LANG
2805
2806 template<class _Tp, class _Compare>
2807 _LIBCPP_NODISCARD_EXT inline
2808 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2809 pair<_Tp, _Tp>
2810 minmax(initializer_list<_Tp> __t, _Compare __comp)
2811 {
2812 typedef typename initializer_list<_Tp>::const_iterator _Iter;
2813 _Iter __first = __t.begin();
2814 _Iter __last = __t.end();
2815 pair<_Tp, _Tp> __result(*__first, *__first);
2816
2817 ++__first;
2818 if (__t.size() % 2 == 0)
2819 {
2820 if (__comp(*__first, __result.first))
2821 __result.first = *__first;
2822 else
2823 __result.second = *__first;
2824 ++__first;
2825 }
2826
2827 while (__first != __last)
2828 {
2829 _Tp __prev = *__first++;
2830 if (__comp(*__first, __prev)) {
2831 if ( __comp(*__first, __result.first)) __result.first = *__first;
2832 if (!__comp(__prev, __result.second)) __result.second = __prev;
2833 }
2834 else {
2835 if ( __comp(__prev, __result.first)) __result.first = __prev;
2836 if (!__comp(*__first, __result.second)) __result.second = *__first;
2837 }
2838
2839 __first++;
2840 }
2841 return __result;
2842 }
2843
2844 template<class _Tp>
2845 _LIBCPP_NODISCARD_EXT inline
2846 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
2847 pair<_Tp, _Tp>
2848 minmax(initializer_list<_Tp> __t)
2849 {
2850 return _VSTD::minmax(__t, __less<_Tp>());
2851 }
2852
2853 #endif // _LIBCPP_CXX03_LANG
2854
2855 // random_shuffle
2856
2857 // __independent_bits_engine
2858
2859 template <unsigned long long _Xp, size_t _Rp>
2860 struct __log2_imp
2861 {
2862 static const size_t value = _Xp & ((unsigned long long)(1) << _Rp) ? _Rp
2863 : __log2_imp<_Xp, _Rp - 1>::value;
2864 };
2865
2866 template <unsigned long long _Xp>
2867 struct __log2_imp<_Xp, 0>
2868 {
2869 static const size_t value = 0;
2870 };
2871
2872 template <size_t _Rp>
2873 struct __log2_imp<0, _Rp>
2874 {
2875 static const size_t value = _Rp + 1;
2876 };
2877
2878 template <class _UIntType, _UIntType _Xp>
2879 struct __log2
2880 {
2881 static const size_t value = __log2_imp<_Xp,
2882 sizeof(_UIntType) * __CHAR_BIT__ - 1>::value;
2883 };
2884
2885 template<class _Engine, class _UIntType>
2886 class __independent_bits_engine
2887 {
2888 public:
2889 // types
2890 typedef _UIntType result_type;
2891
2892 private:
2893 typedef typename _Engine::result_type _Engine_result_type;
2894 typedef typename conditional
2895 <
2896 sizeof(_Engine_result_type) <= sizeof(result_type),
2897 result_type,
2898 _Engine_result_type
2899 >::type _Working_result_type;
2900
2901 _Engine& __e_;
2902 size_t __w_;
2903 size_t __w0_;
2904 size_t __n_;
2905 size_t __n0_;
2906 _Working_result_type __y0_;
2907 _Working_result_type __y1_;
2908 _Engine_result_type __mask0_;
2909 _Engine_result_type __mask1_;
2910
2911 #ifdef _LIBCPP_CXX03_LANG
2912 static const _Working_result_type _Rp = _Engine::_Max - _Engine::_Min
2913 + _Working_result_type(1);
2914 #else
2915 static _LIBCPP_CONSTEXPR const _Working_result_type _Rp = _Engine::max() - _Engine::min()
2916 + _Working_result_type(1);
2917 #endif
2918 static _LIBCPP_CONSTEXPR const size_t __m = __log2<_Working_result_type, _Rp>::value;
2919 static _LIBCPP_CONSTEXPR const size_t _WDt = numeric_limits<_Working_result_type>::digits;
2920 static _LIBCPP_CONSTEXPR const size_t _EDt = numeric_limits<_Engine_result_type>::digits;
2921
2922 public:
2923 // constructors and seeding functions
2924 __independent_bits_engine(_Engine& __e, size_t __w);
2925
2926 // generating functions
2927 result_type operator()() {return __eval(integral_constant<bool, _Rp != 0>());}
2928
2929 private:
2930 result_type __eval(false_type);
2931 result_type __eval(true_type);
2932 };
2933
2934 template<class _Engine, class _UIntType>
2935 __independent_bits_engine<_Engine, _UIntType>
2936 ::__independent_bits_engine(_Engine& __e, size_t __w)
2937 : __e_(__e),
2938 __w_(__w)
2939 {
2940 __n_ = __w_ / __m + (__w_ % __m != 0);
2941 __w0_ = __w_ / __n_;
2942 if (_Rp == 0)
2943 __y0_ = _Rp;
2944 else if (__w0_ < _WDt)
2945 __y0_ = (_Rp >> __w0_) << __w0_;
2946 else
2947 __y0_ = 0;
2948 if (_Rp - __y0_ > __y0_ / __n_)
2949 {
2950 ++__n_;
2951 __w0_ = __w_ / __n_;
2952 if (__w0_ < _WDt)
2953 __y0_ = (_Rp >> __w0_) << __w0_;
2954 else
2955 __y0_ = 0;
2956 }
2957 __n0_ = __n_ - __w_ % __n_;
2958 if (__w0_ < _WDt - 1)
2959 __y1_ = (_Rp >> (__w0_ + 1)) << (__w0_ + 1);
2960 else
2961 __y1_ = 0;
2962 __mask0_ = __w0_ > 0 ? _Engine_result_type(~0) >> (_EDt - __w0_) :
2963 _Engine_result_type(0);
2964 __mask1_ = __w0_ < _EDt - 1 ?
2965 _Engine_result_type(~0) >> (_EDt - (__w0_ + 1)) :
2966 _Engine_result_type(~0);
2967 }
2968
2969 template<class _Engine, class _UIntType>
2970 inline
2971 _UIntType
2972 __independent_bits_engine<_Engine, _UIntType>::__eval(false_type)
2973 {
2974 return static_cast<result_type>(__e_() & __mask0_);
2975 }
2976
2977 template<class _Engine, class _UIntType>
2978 _UIntType
2979 __independent_bits_engine<_Engine, _UIntType>::__eval(true_type)
2980 {
2981 const size_t _WRt = numeric_limits<result_type>::digits;
2982 result_type _Sp = 0;
2983 for (size_t __k = 0; __k < __n0_; ++__k)
2984 {
2985 _Engine_result_type __u;
2986 do
2987 {
2988 __u = __e_() - _Engine::min();
2989 } while (__u >= __y0_);
2990 if (__w0_ < _WRt)
2991 _Sp <<= __w0_;
2992 else
2993 _Sp = 0;
2994 _Sp += __u & __mask0_;
2995 }
2996 for (size_t __k = __n0_; __k < __n_; ++__k)
2997 {
2998 _Engine_result_type __u;
2999 do
3000 {
3001 __u = __e_() - _Engine::min();
3002 } while (__u >= __y1_);
3003 if (__w0_ < _WRt - 1)
3004 _Sp <<= __w0_ + 1;
3005 else
3006 _Sp = 0;
3007 _Sp += __u & __mask1_;
3008 }
3009 return _Sp;
3010 }
3011
3012 // uniform_int_distribution
3013
3014 template<class _IntType = int>
3015 class uniform_int_distribution
3016 {
3017 public:
3018 // types
3019 typedef _IntType result_type;
3020
3021 class param_type
3022 {
3023 result_type __a_;
3024 result_type __b_;
3025 public:
3026 typedef uniform_int_distribution distribution_type;
3027
3028 explicit param_type(result_type __a = 0,
3029 result_type __b = numeric_limits<result_type>::max())
3030 : __a_(__a), __b_(__b) {}
3031
3032 result_type a() const {return __a_;}
3033 result_type b() const {return __b_;}
3034
3035 friend bool operator==(const param_type& __x, const param_type& __y)
3036 {return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;}
3037 friend bool operator!=(const param_type& __x, const param_type& __y)
3038 {return !(__x == __y);}
3039 };
3040
3041 private:
3042 param_type __p_;
3043
3044 public:
3045 // constructors and reset functions
3046 #ifndef _LIBCPP_CXX03_LANG
3047 uniform_int_distribution() : uniform_int_distribution(0) {}
3048 explicit uniform_int_distribution(
3049 result_type __a, result_type __b = numeric_limits<result_type>::max())
3050 : __p_(param_type(__a, __b)) {}
3051 #else
3052 explicit uniform_int_distribution(
3053 result_type __a = 0,
3054 result_type __b = numeric_limits<result_type>::max())
3055 : __p_(param_type(__a, __b)) {}
3056 #endif
3057 explicit uniform_int_distribution(const param_type& __p) : __p_(__p) {}
3058 void reset() {}
3059
3060 // generating functions
3061 template<class _URNG> result_type operator()(_URNG& __g)
3062 {return (*this)(__g, __p_);}
3063 template<class _URNG> result_type operator()(_URNG& __g, const param_type& __p);
3064
3065 // property functions
3066 result_type a() const {return __p_.a();}
3067 result_type b() const {return __p_.b();}
3068
3069 param_type param() const {return __p_;}
3070 void param(const param_type& __p) {__p_ = __p;}
3071
3072 result_type min() const {return a();}
3073 result_type max() const {return b();}
3074
3075 friend bool operator==(const uniform_int_distribution& __x,
3076 const uniform_int_distribution& __y)
3077 {return __x.__p_ == __y.__p_;}
3078 friend bool operator!=(const uniform_int_distribution& __x,
3079 const uniform_int_distribution& __y)
3080 {return !(__x == __y);}
3081 };
3082
3083 template<class _IntType>
3084 template<class _URNG>
3085 typename uniform_int_distribution<_IntType>::result_type
3086 uniform_int_distribution<_IntType>::operator()(_URNG& __g, const param_type& __p)
3087 _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
3088 {
3089 typedef typename conditional<sizeof(result_type) <= sizeof(uint32_t),
3090 uint32_t, uint64_t>::type _UIntType;
3091 const _UIntType _Rp = _UIntType(__p.b()) - _UIntType(__p.a()) + _UIntType(1);
3092 if (_Rp == 1)
3093 return __p.a();
3094 const size_t _Dt = numeric_limits<_UIntType>::digits;
3095 typedef __independent_bits_engine<_URNG, _UIntType> _Eng;
3096 if (_Rp == 0)
3097 return static_cast<result_type>(_Eng(__g, _Dt)());
3098 size_t __w = _Dt - __libcpp_clz(_Rp) - 1;
3099 if ((_Rp & (numeric_limits<_UIntType>::max() >> (_Dt - __w))) != 0)
3100 ++__w;
3101 _Eng __e(__g, __w);
3102 _UIntType __u;
3103 do
3104 {
3105 __u = __e();
3106 } while (__u >= _Rp);
3107 return static_cast<result_type>(__u + __p.a());
3108 }
3109
3110 #if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE) \
3111 || defined(_LIBCPP_BUILDING_LIBRARY)
3112 class _LIBCPP_TYPE_VIS __rs_default;
3113
3114 _LIBCPP_FUNC_VIS __rs_default __rs_get();
3115
3116 class _LIBCPP_TYPE_VIS __rs_default
3117 {
3118 static unsigned __c_;
3119
3120 __rs_default();
3121 public:
3122 typedef uint_fast32_t result_type;
3123
3124 static const result_type _Min = 0;
3125 static const result_type _Max = 0xFFFFFFFF;
3126
3127 __rs_default(const __rs_default&);
3128 ~__rs_default();
3129
3130 result_type operator()();
3131
3132 static _LIBCPP_CONSTEXPR result_type min() {return _Min;}
3133 static _LIBCPP_CONSTEXPR result_type max() {return _Max;}
3134
3135 friend _LIBCPP_FUNC_VIS __rs_default __rs_get();
3136 };
3137
3138 _LIBCPP_FUNC_VIS __rs_default __rs_get();
3139
3140 template <class _RandomAccessIterator>
3141 _LIBCPP_DEPRECATED_IN_CXX14 void
3142 random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
3143 {
3144 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
3145 typedef uniform_int_distribution<ptrdiff_t> _Dp;
3146 typedef typename _Dp::param_type _Pp;
3147 difference_type __d = __last - __first;
3148 if (__d > 1)
3149 {
3150 _Dp __uid;
3151 __rs_default __g = __rs_get();
3152 for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
3153 {
3154 difference_type __i = __uid(__g, _Pp(0, __d));
3155 if (__i != difference_type(0))
3156 swap(*__first, *(__first + __i));
3157 }
3158 }
3159 }
3160
3161 template <class _RandomAccessIterator, class _RandomNumberGenerator>
3162 _LIBCPP_DEPRECATED_IN_CXX14 void
3163 random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
3164 #ifndef _LIBCPP_CXX03_LANG
3165 _RandomNumberGenerator&& __rand)
3166 #else
3167 _RandomNumberGenerator& __rand)
3168 #endif
3169 {
3170 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
3171 difference_type __d = __last - __first;
3172 if (__d > 1)
3173 {
3174 for (--__last; __first < __last; ++__first, (void) --__d)
3175 {
3176 difference_type __i = __rand(__d);
3177 if (__i != difference_type(0))
3178 swap(*__first, *(__first + __i));
3179 }
3180 }
3181 }
3182 #endif
3183
3184 template <class _PopulationIterator, class _SampleIterator, class _Distance,
3185 class _UniformRandomNumberGenerator>
3186 _LIBCPP_INLINE_VISIBILITY
3187 _SampleIterator __sample(_PopulationIterator __first,
3188 _PopulationIterator __last, _SampleIterator __output_iter,
3189 _Distance __n,
3190 _UniformRandomNumberGenerator & __g,
3191 input_iterator_tag) {
3192
3193 _Distance __k = 0;
3194 for (; __first != __last && __k < __n; ++__first, (void) ++__k)
3195 __output_iter[__k] = *__first;
3196 _Distance __sz = __k;
3197 for (; __first != __last; ++__first, (void) ++__k) {
3198 _Distance __r = uniform_int_distribution<_Distance>(0, __k)(__g);
3199 if (__r < __sz)
3200 __output_iter[__r] = *__first;
3201 }
3202 return __output_iter + _VSTD::min(__n, __k);
3203 }
3204
3205 template <class _PopulationIterator, class _SampleIterator, class _Distance,
3206 class _UniformRandomNumberGenerator>
3207 _LIBCPP_INLINE_VISIBILITY
3208 _SampleIterator __sample(_PopulationIterator __first,
3209 _PopulationIterator __last, _SampleIterator __output_iter,
3210 _Distance __n,
3211 _UniformRandomNumberGenerator& __g,
3212 forward_iterator_tag) {
3213 _Distance __unsampled_sz = _VSTD::distance(__first, __last);
3214 for (__n = _VSTD::min(__n, __unsampled_sz); __n != 0; ++__first) {
3215 _Distance __r = uniform_int_distribution<_Distance>(0, --__unsampled_sz)(__g);
3216 if (__r < __n) {
3217 *__output_iter++ = *__first;
3218 --__n;
3219 }
3220 }
3221 return __output_iter;
3222 }
3223
3224 template <class _PopulationIterator, class _SampleIterator, class _Distance,
3225 class _UniformRandomNumberGenerator>
3226 _LIBCPP_INLINE_VISIBILITY
3227 _SampleIterator __sample(_PopulationIterator __first,
3228 _PopulationIterator __last, _SampleIterator __output_iter,
3229 _Distance __n, _UniformRandomNumberGenerator& __g) {
3230 typedef typename iterator_traits<_PopulationIterator>::iterator_category
3231 _PopCategory;
3232 typedef typename iterator_traits<_PopulationIterator>::difference_type
3233 _Difference;
3234 static_assert(__is_cpp17_forward_iterator<_PopulationIterator>::value ||
3235 __is_cpp17_random_access_iterator<_SampleIterator>::value,
3236 "SampleIterator must meet the requirements of RandomAccessIterator");
3237 typedef typename common_type<_Distance, _Difference>::type _CommonType;
3238 _LIBCPP_ASSERT(__n >= 0, "N must be a positive number.");
3239 return _VSTD::__sample(
3240 __first, __last, __output_iter, _CommonType(__n),
3241 __g, _PopCategory());
3242 }
3243
3244 #if _LIBCPP_STD_VER > 14
3245 template <class _PopulationIterator, class _SampleIterator, class _Distance,
3246 class _UniformRandomNumberGenerator>
3247 inline _LIBCPP_INLINE_VISIBILITY
3248 _SampleIterator sample(_PopulationIterator __first,
3249 _PopulationIterator __last, _SampleIterator __output_iter,
3250 _Distance __n, _UniformRandomNumberGenerator&& __g) {
3251 return _VSTD::__sample(__first, __last, __output_iter, __n, __g);
3252 }
3253 #endif // _LIBCPP_STD_VER > 14
3254
3255 template<class _RandomAccessIterator, class _UniformRandomNumberGenerator>
3256 void shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
3257 _UniformRandomNumberGenerator&& __g)
3258 {
3259 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
3260 typedef uniform_int_distribution<ptrdiff_t> _Dp;
3261 typedef typename _Dp::param_type _Pp;
3262 difference_type __d = __last - __first;
3263 if (__d > 1)
3264 {
3265 _Dp __uid;
3266 for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
3267 {
3268 difference_type __i = __uid(__g, _Pp(0, __d));
3269 if (__i != difference_type(0))
3270 swap(*__first, *(__first + __i));
3271 }
3272 }
3273 }
3274
3275 #if _LIBCPP_STD_VER > 17
3276
3277 // shift_left, shift_right
3278
3279 template <class _ForwardIterator>
3280 inline _LIBCPP_INLINE_VISIBILITY constexpr
3281 _ForwardIterator
3282 shift_left(_ForwardIterator __first, _ForwardIterator __last,
3283 typename iterator_traits<_ForwardIterator>::difference_type __n)
3284 {
3285 if (__n == 0) {
3286 return __last;
3287 }
3288
3289 _ForwardIterator __m = __first;
3290 if constexpr (__is_cpp17_random_access_iterator<_ForwardIterator>::value) {
3291 if (__n >= __last - __first) {
3292 return __first;
3293 }
3294 __m += __n;
3295 } else {
3296 for (; __n > 0; --__n) {
3297 if (__m == __last) {
3298 return __first;
3299 }
3300 ++__m;
3301 }
3302 }
3303 return _VSTD::move(__m, __last, __first);
3304 }
3305
3306 template <class _ForwardIterator>
3307 inline _LIBCPP_INLINE_VISIBILITY constexpr
3308 _ForwardIterator
3309 shift_right(_ForwardIterator __first, _ForwardIterator __last,
3310 typename iterator_traits<_ForwardIterator>::difference_type __n)
3311 {
3312 if (__n == 0) {
3313 return __first;
3314 }
3315
3316 if constexpr (__is_cpp17_random_access_iterator<_ForwardIterator>::value) {
3317 decltype(__n) __d = __last - __first;
3318 if (__n >= __d) {
3319 return __last;
3320 }
3321 _ForwardIterator __m = __first + (__d - __n);
3322 return _VSTD::move_backward(__first, __m, __last);
3323 } else if constexpr (__is_cpp17_bidirectional_iterator<_ForwardIterator>::value) {
3324 _ForwardIterator __m = __last;
3325 for (; __n > 0; --__n) {
3326 if (__m == __first) {
3327 return __last;
3328 }
3329 --__m;
3330 }
3331 return _VSTD::move_backward(__first, __m, __last);
3332 } else {
3333 _ForwardIterator __ret = __first;
3334 for (; __n > 0; --__n) {
3335 if (__ret == __last) {
3336 return __last;
3337 }
3338 ++__ret;
3339 }
3340
3341 // We have an __n-element scratch space from __first to __ret.
3342 // Slide an __n-element window [__trail, __lead) from left to right.
3343 // We're essentially doing swap_ranges(__first, __ret, __trail, __lead)
3344 // over and over; but once __lead reaches __last we needn't bother
3345 // to save the values of elements [__trail, __last).
3346
3347 auto __trail = __first;
3348 auto __lead = __ret;
3349 while (__trail != __ret) {
3350 if (__lead == __last) {
3351 _VSTD::move(__first, __trail, __ret);
3352 return __ret;
3353 }
3354 ++__trail;
3355 ++__lead;
3356 }
3357
3358 _ForwardIterator __mid = __first;
3359 while (true) {
3360 if (__lead == __last) {
3361 __trail = _VSTD::move(__mid, __ret, __trail);
3362 _VSTD::move(__first, __mid, __trail);
3363 return __ret;
3364 }
3365 swap(*__mid, *__trail);
3366 ++__mid;
3367 ++__trail;
3368 ++__lead;
3369 if (__mid == __ret) {
3370 __mid = __first;
3371 }
3372 }
3373 }
3374 }
3375
3376 #endif // _LIBCPP_STD_VER > 17
3377
3378 // is_partitioned
3379
3380 template <class _InputIterator, class _Predicate>
3381 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
3382 is_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred)
3383 {
3384 for (; __first != __last; ++__first)
3385 if (!__pred(*__first))
3386 break;
3387 if ( __first == __last )
3388 return true;
3389 ++__first;
3390 for (; __first != __last; ++__first)
3391 if (__pred(*__first))
3392 return false;
3393 return true;
3394 }
3395
3396 // partition
3397
3398 template <class _Predicate, class _ForwardIterator>
3399 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
3400 __partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, forward_iterator_tag)
3401 {
3402 while (true)
3403 {
3404 if (__first == __last)
3405 return __first;
3406 if (!__pred(*__first))
3407 break;
3408 ++__first;
3409 }
3410 for (_ForwardIterator __p = __first; ++__p != __last;)
3411 {
3412 if (__pred(*__p))
3413 {
3414 swap(*__first, *__p);
3415 ++__first;
3416 }
3417 }
3418 return __first;
3419 }
3420
3421 template <class _Predicate, class _BidirectionalIterator>
3422 _LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator
3423 __partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
3424 bidirectional_iterator_tag)
3425 {
3426 while (true)
3427 {
3428 while (true)
3429 {
3430 if (__first == __last)
3431 return __first;
3432 if (!__pred(*__first))
3433 break;
3434 ++__first;
3435 }
3436 do
3437 {
3438 if (__first == --__last)
3439 return __first;
3440 } while (!__pred(*__last));
3441 swap(*__first, *__last);
3442 ++__first;
3443 }
3444 }
3445
3446 template <class _ForwardIterator, class _Predicate>
3447 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
3448 _ForwardIterator
3449 partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
3450 {
3451 return _VSTD::__partition<typename add_lvalue_reference<_Predicate>::type>
3452 (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
3453 }
3454
3455 // partition_copy
3456
3457 template <class _InputIterator, class _OutputIterator1,
3458 class _OutputIterator2, class _Predicate>
3459 _LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_OutputIterator1, _OutputIterator2>
3460 partition_copy(_InputIterator __first, _InputIterator __last,
3461 _OutputIterator1 __out_true, _OutputIterator2 __out_false,
3462 _Predicate __pred)
3463 {
3464 for (; __first != __last; ++__first)
3465 {
3466 if (__pred(*__first))
3467 {
3468 *__out_true = *__first;
3469 ++__out_true;
3470 }
3471 else
3472 {
3473 *__out_false = *__first;
3474 ++__out_false;
3475 }
3476 }
3477 return pair<_OutputIterator1, _OutputIterator2>(__out_true, __out_false);
3478 }
3479
3480 // partition_point
3481
3482 template<class _ForwardIterator, class _Predicate>
3483 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
3484 partition_point(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
3485 {
3486 typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
3487 difference_type __len = _VSTD::distance(__first, __last);
3488 while (__len != 0)
3489 {
3490 difference_type __l2 = _VSTD::__half_positive(__len);
3491 _ForwardIterator __m = __first;
3492 _VSTD::advance(__m, __l2);
3493 if (__pred(*__m))
3494 {
3495 __first = ++__m;
3496 __len -= __l2 + 1;
3497 }
3498 else
3499 __len = __l2;
3500 }
3501 return __first;
3502 }
3503
3504 // stable_partition
3505
3506 template <class _Predicate, class _ForwardIterator, class _Distance, class _Pair>
3507 _ForwardIterator
3508 __stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
3509 _Distance __len, _Pair __p, forward_iterator_tag __fit)
3510 {
3511 // *__first is known to be false
3512 // __len >= 1
3513 if (__len == 1)
3514 return __first;
3515 if (__len == 2)
3516 {
3517 _ForwardIterator __m = __first;
3518 if (__pred(*++__m))
3519 {
3520 swap(*__first, *__m);
3521 return __m;
3522 }
3523 return __first;
3524 }
3525 if (__len <= __p.second)
3526 { // The buffer is big enough to use
3527 typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3528 __destruct_n __d(0);
3529 unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
3530 // Move the falses into the temporary buffer, and the trues to the front of the line
3531 // Update __first to always point to the end of the trues
3532 value_type* __t = __p.first;
3533 ::new ((void*)__t) value_type(_VSTD::move(*__first));
3534 __d.template __incr<value_type>();
3535 ++__t;
3536 _ForwardIterator __i = __first;
3537 while (++__i != __last)
3538 {
3539 if (__pred(*__i))
3540 {
3541 *__first = _VSTD::move(*__i);
3542 ++__first;
3543 }
3544 else
3545 {
3546 ::new ((void*)__t) value_type(_VSTD::move(*__i));
3547 __d.template __incr<value_type>();
3548 ++__t;
3549 }
3550 }
3551 // All trues now at start of range, all falses in buffer
3552 // Move falses back into range, but don't mess up __first which points to first false
3553 __i = __first;
3554 for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void) ++__i)
3555 *__i = _VSTD::move(*__t2);
3556 // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
3557 return __first;
3558 }
3559 // Else not enough buffer, do in place
3560 // __len >= 3
3561 _ForwardIterator __m = __first;
3562 _Distance __len2 = __len / 2; // __len2 >= 2
3563 _VSTD::advance(__m, __len2);
3564 // recurse on [__first, __m), *__first know to be false
3565 // F?????????????????
3566 // f m l
3567 typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
3568 _ForwardIterator __first_false = _VSTD::__stable_partition<_PredRef>(__first, __m, __pred, __len2, __p, __fit);
3569 // TTTFFFFF??????????
3570 // f ff m l
3571 // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
3572 _ForwardIterator __m1 = __m;
3573 _ForwardIterator __second_false = __last;
3574 _Distance __len_half = __len - __len2;
3575 while (__pred(*__m1))
3576 {
3577 if (++__m1 == __last)
3578 goto __second_half_done;
3579 --__len_half;
3580 }
3581 // TTTFFFFFTTTF??????
3582 // f ff m m1 l
3583 __second_false = _VSTD::__stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __fit);
3584 __second_half_done:
3585 // TTTFFFFFTTTTTFFFFF
3586 // f ff m sf l
3587 return _VSTD::rotate(__first_false, __m, __second_false);
3588 // TTTTTTTTFFFFFFFFFF
3589 // |
3590 }
3591
3592 struct __return_temporary_buffer
3593 {
3594 template <class _Tp>
3595 _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) const {_VSTD::return_temporary_buffer(__p);}
3596 };
3597
3598 template <class _Predicate, class _ForwardIterator>
3599 _ForwardIterator
3600 __stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
3601 forward_iterator_tag)
3602 {
3603 const unsigned __alloc_limit = 3; // might want to make this a function of trivial assignment
3604 // Either prove all true and return __first or point to first false
3605 while (true)
3606 {
3607 if (__first == __last)
3608 return __first;
3609 if (!__pred(*__first))
3610 break;
3611 ++__first;
3612 }
3613 // We now have a reduced range [__first, __last)
3614 // *__first is known to be false
3615 typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
3616 typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3617 difference_type __len = _VSTD::distance(__first, __last);
3618 pair<value_type*, ptrdiff_t> __p(0, 0);
3619 unique_ptr<value_type, __return_temporary_buffer> __h;
3620 if (__len >= __alloc_limit)
3621 {
3622 __p = _VSTD::get_temporary_buffer<value_type>(__len);
3623 __h.reset(__p.first);
3624 }
3625 return _VSTD::__stable_partition<typename add_lvalue_reference<_Predicate>::type>
3626 (__first, __last, __pred, __len, __p, forward_iterator_tag());
3627 }
3628
3629 template <class _Predicate, class _BidirectionalIterator, class _Distance, class _Pair>
3630 _BidirectionalIterator
3631 __stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
3632 _Distance __len, _Pair __p, bidirectional_iterator_tag __bit)
3633 {
3634 // *__first is known to be false
3635 // *__last is known to be true
3636 // __len >= 2
3637 if (__len == 2)
3638 {
3639 swap(*__first, *__last);
3640 return __last;
3641 }
3642 if (__len == 3)
3643 {
3644 _BidirectionalIterator __m = __first;
3645 if (__pred(*++__m))
3646 {
3647 swap(*__first, *__m);
3648 swap(*__m, *__last);
3649 return __last;
3650 }
3651 swap(*__m, *__last);
3652 swap(*__first, *__m);
3653 return __m;
3654 }
3655 if (__len <= __p.second)
3656 { // The buffer is big enough to use
3657 typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
3658 __destruct_n __d(0);
3659 unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
3660 // Move the falses into the temporary buffer, and the trues to the front of the line
3661 // Update __first to always point to the end of the trues
3662 value_type* __t = __p.first;
3663 ::new ((void*)__t) value_type(_VSTD::move(*__first));
3664 __d.template __incr<value_type>();
3665 ++__t;
3666 _BidirectionalIterator __i = __first;
3667 while (++__i != __last)
3668 {
3669 if (__pred(*__i))
3670 {
3671 *__first = _VSTD::move(*__i);
3672 ++__first;
3673 }
3674 else
3675 {
3676 ::new ((void*)__t) value_type(_VSTD::move(*__i));
3677 __d.template __incr<value_type>();
3678 ++__t;
3679 }
3680 }
3681 // move *__last, known to be true
3682 *__first = _VSTD::move(*__i);
3683 __i = ++__first;
3684 // All trues now at start of range, all falses in buffer
3685 // Move falses back into range, but don't mess up __first which points to first false
3686 for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void) ++__i)
3687 *__i = _VSTD::move(*__t2);
3688 // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
3689 return __first;
3690 }
3691 // Else not enough buffer, do in place
3692 // __len >= 4
3693 _BidirectionalIterator __m = __first;
3694 _Distance __len2 = __len / 2; // __len2 >= 2
3695 _VSTD::advance(__m, __len2);
3696 // recurse on [__first, __m-1], except reduce __m-1 until *(__m-1) is true, *__first know to be false
3697 // F????????????????T
3698 // f m l
3699 _BidirectionalIterator __m1 = __m;
3700 _BidirectionalIterator __first_false = __first;
3701 _Distance __len_half = __len2;
3702 while (!__pred(*--__m1))
3703 {
3704 if (__m1 == __first)
3705 goto __first_half_done;
3706 --__len_half;
3707 }
3708 // F???TFFF?????????T
3709 // f m1 m l
3710 typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
3711 __first_false = _VSTD::__stable_partition<_PredRef>(__first, __m1, __pred, __len_half, __p, __bit);
3712 __first_half_done:
3713 // TTTFFFFF?????????T
3714 // f ff m l
3715 // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
3716 __m1 = __m;
3717 _BidirectionalIterator __second_false = __last;
3718 ++__second_false;
3719 __len_half = __len - __len2;
3720 while (__pred(*__m1))
3721 {
3722 if (++__m1 == __last)
3723 goto __second_half_done;
3724 --__len_half;
3725 }
3726 // TTTFFFFFTTTF?????T
3727 // f ff m m1 l
3728 __second_false = _VSTD::__stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __bit);
3729 __second_half_done:
3730 // TTTFFFFFTTTTTFFFFF
3731 // f ff m sf l
3732 return _VSTD::rotate(__first_false, __m, __second_false);
3733 // TTTTTTTTFFFFFFFFFF
3734 // |
3735 }
3736
3737 template <class _Predicate, class _BidirectionalIterator>
3738 _BidirectionalIterator
3739 __stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
3740 bidirectional_iterator_tag)
3741 {
3742 typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
3743 typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
3744 const difference_type __alloc_limit = 4; // might want to make this a function of trivial assignment
3745 // Either prove all true and return __first or point to first false
3746 while (true)
3747 {
3748 if (__first == __last)
3749 return __first;
3750 if (!__pred(*__first))
3751 break;
3752 ++__first;
3753 }
3754 // __first points to first false, everything prior to __first is already set.
3755 // Either prove [__first, __last) is all false and return __first, or point __last to last true
3756 do
3757 {
3758 if (__first == --__last)
3759 return __first;
3760 } while (!__pred(*__last));
3761 // We now have a reduced range [__first, __last]
3762 // *__first is known to be false
3763 // *__last is known to be true
3764 // __len >= 2
3765 difference_type __len = _VSTD::distance(__first, __last) + 1;
3766 pair<value_type*, ptrdiff_t> __p(0, 0);
3767 unique_ptr<value_type, __return_temporary_buffer> __h;
3768 if (__len >= __alloc_limit)
3769 {
3770 __p = _VSTD::get_temporary_buffer<value_type>(__len);
3771 __h.reset(__p.first);
3772 }
3773 return _VSTD::__stable_partition<typename add_lvalue_reference<_Predicate>::type>
3774 (__first, __last, __pred, __len, __p, bidirectional_iterator_tag());
3775 }
3776
3777 template <class _ForwardIterator, class _Predicate>
3778 inline _LIBCPP_INLINE_VISIBILITY
3779 _ForwardIterator
3780 stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
3781 {
3782 return _VSTD::__stable_partition<typename add_lvalue_reference<_Predicate>::type>
3783 (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
3784 }
3785
3786 // is_sorted_until
3787
3788 template <class _ForwardIterator, class _Compare>
3789 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
3790 is_sorted_until(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
3791 {
3792 if (__first != __last)
3793 {
3794 _ForwardIterator __i = __first;
3795 while (++__i != __last)
3796 {
3797 if (__comp(*__i, *__first))
3798 return __i;
3799 __first = __i;
3800 }
3801 }
3802 return __last;
3803 }
3804
3805 template<class _ForwardIterator>
3806 _LIBCPP_NODISCARD_EXT inline
3807 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
3808 _ForwardIterator
3809 is_sorted_until(_ForwardIterator __first, _ForwardIterator __last)
3810 {
3811 return _VSTD::is_sorted_until(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
3812 }
3813
3814 // is_sorted
3815
3816 template <class _ForwardIterator, class _Compare>
3817 _LIBCPP_NODISCARD_EXT inline
3818 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
3819 bool
3820 is_sorted(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
3821 {
3822 return _VSTD::is_sorted_until(__first, __last, __comp) == __last;
3823 }
3824
3825 template<class _ForwardIterator>
3826 _LIBCPP_NODISCARD_EXT inline
3827 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
3828 bool
3829 is_sorted(_ForwardIterator __first, _ForwardIterator __last)
3830 {
3831 return _VSTD::is_sorted(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
3832 }
3833
3834 // sort
3835
3836 // stable, 2-3 compares, 0-2 swaps
3837
3838 template <class _Compare, class _ForwardIterator>
3839 _LIBCPP_CONSTEXPR_AFTER_CXX11 unsigned
3840 __sort3(_ForwardIterator __x, _ForwardIterator __y, _ForwardIterator __z, _Compare __c)
3841 {
3842 unsigned __r = 0;
3843 if (!__c(*__y, *__x)) // if x <= y
3844 {
3845 if (!__c(*__z, *__y)) // if y <= z
3846 return __r; // x <= y && y <= z
3847 // x <= y && y > z
3848 swap(*__y, *__z); // x <= z && y < z
3849 __r = 1;
3850 if (__c(*__y, *__x)) // if x > y
3851 {
3852 swap(*__x, *__y); // x < y && y <= z
3853 __r = 2;
3854 }
3855 return __r; // x <= y && y < z
3856 }
3857 if (__c(*__z, *__y)) // x > y, if y > z
3858 {
3859 swap(*__x, *__z); // x < y && y < z
3860 __r = 1;
3861 return __r;
3862 }
3863 swap(*__x, *__y); // x > y && y <= z
3864 __r = 1; // x < y && x <= z
3865 if (__c(*__z, *__y)) // if y > z
3866 {
3867 swap(*__y, *__z); // x <= y && y < z
3868 __r = 2;
3869 }
3870 return __r;
3871 } // x <= y && y <= z
3872
3873 // stable, 3-6 compares, 0-5 swaps
3874
3875 template <class _Compare, class _ForwardIterator>
3876 unsigned
3877 __sort4(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
3878 _ForwardIterator __x4, _Compare __c)
3879 {
3880 unsigned __r = _VSTD::__sort3<_Compare>(__x1, __x2, __x3, __c);
3881 if (__c(*__x4, *__x3))
3882 {
3883 swap(*__x3, *__x4);
3884 ++__r;
3885 if (__c(*__x3, *__x2))
3886 {
3887 swap(*__x2, *__x3);
3888 ++__r;
3889 if (__c(*__x2, *__x1))
3890 {
3891 swap(*__x1, *__x2);
3892 ++__r;
3893 }
3894 }
3895 }
3896 return __r;
3897 }
3898
3899 // stable, 4-10 compares, 0-9 swaps
3900
3901 template <class _Compare, class _ForwardIterator>
3902 _LIBCPP_HIDDEN
3903 unsigned
3904 __sort5(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
3905 _ForwardIterator __x4, _ForwardIterator __x5, _Compare __c)
3906 {
3907 unsigned __r = _VSTD::__sort4<_Compare>(__x1, __x2, __x3, __x4, __c);
3908 if (__c(*__x5, *__x4))
3909 {
3910 swap(*__x4, *__x5);
3911 ++__r;
3912 if (__c(*__x4, *__x3))
3913 {
3914 swap(*__x3, *__x4);
3915 ++__r;
3916 if (__c(*__x3, *__x2))
3917 {
3918 swap(*__x2, *__x3);
3919 ++__r;
3920 if (__c(*__x2, *__x1))
3921 {
3922 swap(*__x1, *__x2);
3923 ++__r;
3924 }
3925 }
3926 }
3927 }
3928 return __r;
3929 }
3930
3931 // Assumes size > 0
3932 template <class _Compare, class _BidirectionalIterator>
3933 _LIBCPP_CONSTEXPR_AFTER_CXX11 void
3934 __selection_sort(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
3935 {
3936 _BidirectionalIterator __lm1 = __last;
3937 for (--__lm1; __first != __lm1; ++__first)
3938 {
3939 _BidirectionalIterator __i = _VSTD::min_element<_BidirectionalIterator,
3940 typename add_lvalue_reference<_Compare>::type>
3941 (__first, __last, __comp);
3942 if (__i != __first)
3943 swap(*__first, *__i);
3944 }
3945 }
3946
3947 template <class _Compare, class _BidirectionalIterator>
3948 void
3949 __insertion_sort(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
3950 {
3951 typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
3952 if (__first != __last)
3953 {
3954 _BidirectionalIterator __i = __first;
3955 for (++__i; __i != __last; ++__i)
3956 {
3957 _BidirectionalIterator __j = __i;
3958 value_type __t(_VSTD::move(*__j));
3959 for (_BidirectionalIterator __k = __i; __k != __first && __comp(__t, *--__k); --__j)
3960 *__j = _VSTD::move(*__k);
3961 *__j = _VSTD::move(__t);
3962 }
3963 }
3964 }
3965
3966 template <class _Compare, class _RandomAccessIterator>
3967 void
3968 __insertion_sort_3(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
3969 {
3970 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
3971 _RandomAccessIterator __j = __first+2;
3972 _VSTD::__sort3<_Compare>(__first, __first+1, __j, __comp);
3973 for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
3974 {
3975 if (__comp(*__i, *__j))
3976 {
3977 value_type __t(_VSTD::move(*__i));
3978 _RandomAccessIterator __k = __j;
3979 __j = __i;
3980 do
3981 {
3982 *__j = _VSTD::move(*__k);
3983 __j = __k;
3984 } while (__j != __first && __comp(__t, *--__k));
3985 *__j = _VSTD::move(__t);
3986 }
3987 __j = __i;
3988 }
3989 }
3990
3991 template <class _Compare, class _RandomAccessIterator>
3992 bool
3993 __insertion_sort_incomplete(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
3994 {
3995 switch (__last - __first)
3996 {
3997 case 0:
3998 case 1:
3999 return true;
4000 case 2:
4001 if (__comp(*--__last, *__first))
4002 swap(*__first, *__last);
4003 return true;
4004 case 3:
4005 _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
4006 return true;
4007 case 4:
4008 _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
4009 return true;
4010 case 5:
4011 _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
4012 return true;
4013 }
4014 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
4015 _RandomAccessIterator __j = __first+2;
4016 _VSTD::__sort3<_Compare>(__first, __first+1, __j, __comp);
4017 const unsigned __limit = 8;
4018 unsigned __count = 0;
4019 for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
4020 {
4021 if (__comp(*__i, *__j))
4022 {
4023 value_type __t(_VSTD::move(*__i));
4024 _RandomAccessIterator __k = __j;
4025 __j = __i;
4026 do
4027 {
4028 *__j = _VSTD::move(*__k);
4029 __j = __k;
4030 } while (__j != __first && __comp(__t, *--__k));
4031 *__j = _VSTD::move(__t);
4032 if (++__count == __limit)
4033 return ++__i == __last;
4034 }
4035 __j = __i;
4036 }
4037 return true;
4038 }
4039
4040 template <class _Compare, class _BidirectionalIterator>
4041 void
4042 __insertion_sort_move(_BidirectionalIterator __first1, _BidirectionalIterator __last1,
4043 typename iterator_traits<_BidirectionalIterator>::value_type* __first2, _Compare __comp)
4044 {
4045 typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
4046 if (__first1 != __last1)
4047 {
4048 __destruct_n __d(0);
4049 unique_ptr<value_type, __destruct_n&> __h(__first2, __d);
4050 value_type* __last2 = __first2;
4051 ::new ((void*)__last2) value_type(_VSTD::move(*__first1));
4052 __d.template __incr<value_type>();
4053 for (++__last2; ++__first1 != __last1; ++__last2)
4054 {
4055 value_type* __j2 = __last2;
4056 value_type* __i2 = __j2;
4057 if (__comp(*__first1, *--__i2))
4058 {
4059 ::new ((void*)__j2) value_type(_VSTD::move(*__i2));
4060 __d.template __incr<value_type>();
4061 for (--__j2; __i2 != __first2 && __comp(*__first1, *--__i2); --__j2)
4062 *__j2 = _VSTD::move(*__i2);
4063 *__j2 = _VSTD::move(*__first1);
4064 }
4065 else
4066 {
4067 ::new ((void*)__j2) value_type(_VSTD::move(*__first1));
4068 __d.template __incr<value_type>();
4069 }
4070 }
4071 __h.release();
4072 }
4073 }
4074
4075 template <class _Compare, class _RandomAccessIterator>
4076 void
4077 __sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
4078 {
4079 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
4080 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
4081 const difference_type __limit = is_trivially_copy_constructible<value_type>::value &&
4082 is_trivially_copy_assignable<value_type>::value ? 30 : 6;
4083 while (true)
4084 {
4085 __restart:
4086 difference_type __len = __last - __first;
4087 switch (__len)
4088 {
4089 case 0:
4090 case 1:
4091 return;
4092 case 2:
4093 if (__comp(*--__last, *__first))
4094 swap(*__first, *__last);
4095 return;
4096 case 3:
4097 _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
4098 return;
4099 case 4:
4100 _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
4101 return;
4102 case 5:
4103 _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
4104 return;
4105 }
4106 if (__len <= __limit)
4107 {
4108 _VSTD::__insertion_sort_3<_Compare>(__first, __last, __comp);
4109 return;
4110 }
4111 // __len > 5
4112 _RandomAccessIterator __m = __first;
4113 _RandomAccessIterator __lm1 = __last;
4114 --__lm1;
4115 unsigned __n_swaps;
4116 {
4117 difference_type __delta;
4118 if (__len >= 1000)
4119 {
4120 __delta = __len/2;
4121 __m += __delta;
4122 __delta /= 2;
4123 __n_swaps = _VSTD::__sort5<_Compare>(__first, __first + __delta, __m, __m+__delta, __lm1, __comp);
4124 }
4125 else
4126 {
4127 __delta = __len/2;
4128 __m += __delta;
4129 __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, __lm1, __comp);
4130 }
4131 }
4132 // *__m is median
4133 // partition [__first, __m) < *__m and *__m <= [__m, __last)
4134 // (this inhibits tossing elements equivalent to __m around unnecessarily)
4135 _RandomAccessIterator __i = __first;
4136 _RandomAccessIterator __j = __lm1;
4137 // j points beyond range to be tested, *__m is known to be <= *__lm1
4138 // The search going up is known to be guarded but the search coming down isn't.
4139 // Prime the downward search with a guard.
4140 if (!__comp(*__i, *__m)) // if *__first == *__m
4141 {
4142 // *__first == *__m, *__first doesn't go in first part
4143 // manually guard downward moving __j against __i
4144 while (true)
4145 {
4146 if (__i == --__j)
4147 {
4148 // *__first == *__m, *__m <= all other elements
4149 // Parition instead into [__first, __i) == *__first and *__first < [__i, __last)
4150 ++__i; // __first + 1
4151 __j = __last;
4152 if (!__comp(*__first, *--__j)) // we need a guard if *__first == *(__last-1)
4153 {
4154 while (true)
4155 {
4156 if (__i == __j)
4157 return; // [__first, __last) all equivalent elements
4158 if (__comp(*__first, *__i))
4159 {
4160 swap(*__i, *__j);
4161 ++__n_swaps;
4162 ++__i;
4163 break;
4164 }
4165 ++__i;
4166 }
4167 }
4168 // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
4169 if (__i == __j)
4170 return;
4171 while (true)
4172 {
4173 while (!__comp(*__first, *__i))
4174 ++__i;
4175 while (__comp(*__first, *--__j))
4176 ;
4177 if (__i >= __j)
4178 break;
4179 swap(*__i, *__j);
4180 ++__n_swaps;
4181 ++__i;
4182 }
4183 // [__first, __i) == *__first and *__first < [__i, __last)
4184 // The first part is sorted, sort the second part
4185 // _VSTD::__sort<_Compare>(__i, __last, __comp);
4186 __first = __i;
4187 goto __restart;
4188 }
4189 if (__comp(*__j, *__m))
4190 {
4191 swap(*__i, *__j);
4192 ++__n_swaps;
4193 break; // found guard for downward moving __j, now use unguarded partition
4194 }
4195 }
4196 }
4197 // It is known that *__i < *__m
4198 ++__i;
4199 // j points beyond range to be tested, *__m is known to be <= *__lm1
4200 // if not yet partitioned...
4201 if (__i < __j)
4202 {
4203 // known that *(__i - 1) < *__m
4204 // known that __i <= __m
4205 while (true)
4206 {
4207 // __m still guards upward moving __i
4208 while (__comp(*__i, *__m))
4209 ++__i;
4210 // It is now known that a guard exists for downward moving __j
4211 while (!__comp(*--__j, *__m))
4212 ;
4213 if (__i > __j)
4214 break;
4215 swap(*__i, *__j);
4216 ++__n_swaps;
4217 // It is known that __m != __j
4218 // If __m just moved, follow it
4219 if (__m == __i)
4220 __m = __j;
4221 ++__i;
4222 }
4223 }
4224 // [__first, __i) < *__m and *__m <= [__i, __last)
4225 if (__i != __m && __comp(*__m, *__i))
4226 {
4227 swap(*__i, *__m);
4228 ++__n_swaps;
4229 }
4230 // [__first, __i) < *__i and *__i <= [__i+1, __last)
4231 // If we were given a perfect partition, see if insertion sort is quick...
4232 if (__n_swaps == 0)
4233 {
4234 bool __fs = _VSTD::__insertion_sort_incomplete<_Compare>(__first, __i, __comp);
4235 if (_VSTD::__insertion_sort_incomplete<_Compare>(__i+1, __last, __comp))
4236 {
4237 if (__fs)
4238 return;
4239 __last = __i;
4240 continue;
4241 }
4242 else
4243 {
4244 if (__fs)
4245 {
4246 __first = ++__i;
4247 continue;
4248 }
4249 }
4250 }
4251 // sort smaller range with recursive call and larger with tail recursion elimination
4252 if (__i - __first < __last - __i)
4253 {
4254 _VSTD::__sort<_Compare>(__first, __i, __comp);
4255 // _VSTD::__sort<_Compare>(__i+1, __last, __comp);
4256 __first = ++__i;
4257 }
4258 else
4259 {
4260 _VSTD::__sort<_Compare>(__i+1, __last, __comp);
4261 // _VSTD::__sort<_Compare>(__first, __i, __comp);
4262 __last = __i;
4263 }
4264 }
4265 }
4266
4267 template <class _Compare, class _Tp>
4268 inline _LIBCPP_INLINE_VISIBILITY
4269 void
4270 __sort(_Tp** __first, _Tp** __last, __less<_Tp*>&)
4271 {
4272 __less<uintptr_t> __comp;
4273 _VSTD::__sort<__less<uintptr_t>&, uintptr_t*>((uintptr_t*)__first, (uintptr_t*)__last, __comp);
4274 }
4275
4276 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<char>&, char*>(char*, char*, __less<char>&))
4277 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
4278 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
4279 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
4280 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<short>&, short*>(short*, short*, __less<short>&))
4281 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
4282 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<int>&, int*>(int*, int*, __less<int>&))
4283 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
4284 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long>&, long*>(long*, long*, __less<long>&))
4285 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
4286 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
4287 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long long>&, unsigned long long*>(unsigned long long*, unsigned long long*, __less<unsigned long long>&))
4288 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<float>&, float*>(float*, float*, __less<float>&))
4289 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<double>&, double*>(double*, double*, __less<double>&))
4290 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
4291
4292 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<char>&, char*>(char*, char*, __less<char>&))
4293 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
4294 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
4295 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
4296 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<short>&, short*>(short*, short*, __less<short>&))
4297 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
4298 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<int>&, int*>(int*, int*, __less<int>&))
4299 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
4300 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long>&, long*>(long*, long*, __less<long>&))
4301 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
4302 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
4303 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long long>&, unsigned long long*>(unsigned long long*, unsigned long long*, __less<unsigned long long>&))
4304 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<float>&, float*>(float*, float*, __less<float>&))
4305 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<double>&, double*>(double*, double*, __less<double>&))
4306 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
4307
4308 _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS unsigned __sort5<__less<long double>&, long double*>(long double*, long double*, long double*, long double*, long double*, __less<long double>&))
4309
4310 // lower_bound
4311
4312 template <class _Compare, class _ForwardIterator, class _Tp>
4313 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
4314 __lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
4315 {
4316 typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4317 difference_type __len = _VSTD::distance(__first, __last);
4318 while (__len != 0)
4319 {
4320 difference_type __l2 = _VSTD::__half_positive(__len);
4321 _ForwardIterator __m = __first;
4322 _VSTD::advance(__m, __l2);
4323 if (__comp(*__m, __value_))
4324 {
4325 __first = ++__m;
4326 __len -= __l2 + 1;
4327 }
4328 else
4329 __len = __l2;
4330 }
4331 return __first;
4332 }
4333
4334 template <class _ForwardIterator, class _Tp, class _Compare>
4335 _LIBCPP_NODISCARD_EXT inline
4336 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4337 _ForwardIterator
4338 lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
4339 {
4340 typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4341 return _VSTD::__lower_bound<_Comp_ref>(__first, __last, __value_, __comp);
4342 }
4343
4344 template <class _ForwardIterator, class _Tp>
4345 _LIBCPP_NODISCARD_EXT inline
4346 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4347 _ForwardIterator
4348 lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
4349 {
4350 return _VSTD::lower_bound(__first, __last, __value_,
4351 __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
4352 }
4353
4354 // upper_bound
4355
4356 template <class _Compare, class _ForwardIterator, class _Tp>
4357 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
4358 __upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
4359 {
4360 typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4361 difference_type __len = _VSTD::distance(__first, __last);
4362 while (__len != 0)
4363 {
4364 difference_type __l2 = _VSTD::__half_positive(__len);
4365 _ForwardIterator __m = __first;
4366 _VSTD::advance(__m, __l2);
4367 if (__comp(__value_, *__m))
4368 __len = __l2;
4369 else
4370 {
4371 __first = ++__m;
4372 __len -= __l2 + 1;
4373 }
4374 }
4375 return __first;
4376 }
4377
4378 template <class _ForwardIterator, class _Tp, class _Compare>
4379 _LIBCPP_NODISCARD_EXT inline
4380 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4381 _ForwardIterator
4382 upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
4383 {
4384 typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4385 return _VSTD::__upper_bound<_Comp_ref>(__first, __last, __value_, __comp);
4386 }
4387
4388 template <class _ForwardIterator, class _Tp>
4389 _LIBCPP_NODISCARD_EXT inline
4390 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4391 _ForwardIterator
4392 upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
4393 {
4394 return _VSTD::upper_bound(__first, __last, __value_,
4395 __less<_Tp, typename iterator_traits<_ForwardIterator>::value_type>());
4396 }
4397
4398 // equal_range
4399
4400 template <class _Compare, class _ForwardIterator, class _Tp>
4401 _LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_ForwardIterator, _ForwardIterator>
4402 __equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
4403 {
4404 typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4405 difference_type __len = _VSTD::distance(__first, __last);
4406 while (__len != 0)
4407 {
4408 difference_type __l2 = _VSTD::__half_positive(__len);
4409 _ForwardIterator __m = __first;
4410 _VSTD::advance(__m, __l2);
4411 if (__comp(*__m, __value_))
4412 {
4413 __first = ++__m;
4414 __len -= __l2 + 1;
4415 }
4416 else if (__comp(__value_, *__m))
4417 {
4418 __last = __m;
4419 __len = __l2;
4420 }
4421 else
4422 {
4423 _ForwardIterator __mp1 = __m;
4424 return pair<_ForwardIterator, _ForwardIterator>
4425 (
4426 _VSTD::__lower_bound<_Compare>(__first, __m, __value_, __comp),
4427 _VSTD::__upper_bound<_Compare>(++__mp1, __last, __value_, __comp)
4428 );
4429 }
4430 }
4431 return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
4432 }
4433
4434 template <class _ForwardIterator, class _Tp, class _Compare>
4435 _LIBCPP_NODISCARD_EXT inline
4436 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4437 pair<_ForwardIterator, _ForwardIterator>
4438 equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
4439 {
4440 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4441 return _VSTD::__equal_range<_Comp_ref>(__first, __last, __value_, __comp);
4442 }
4443
4444 template <class _ForwardIterator, class _Tp>
4445 _LIBCPP_NODISCARD_EXT inline
4446 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4447 pair<_ForwardIterator, _ForwardIterator>
4448 equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
4449 {
4450 return _VSTD::equal_range(__first, __last, __value_,
4451 __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
4452 }
4453
4454 // binary_search
4455
4456 template <class _Compare, class _ForwardIterator, class _Tp>
4457 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4458 bool
4459 __binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
4460 {
4461 __first = _VSTD::__lower_bound<_Compare>(__first, __last, __value_, __comp);
4462 return __first != __last && !__comp(__value_, *__first);
4463 }
4464
4465 template <class _ForwardIterator, class _Tp, class _Compare>
4466 _LIBCPP_NODISCARD_EXT inline
4467 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4468 bool
4469 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
4470 {
4471 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4472 return _VSTD::__binary_search<_Comp_ref>(__first, __last, __value_, __comp);
4473 }
4474
4475 template <class _ForwardIterator, class _Tp>
4476 _LIBCPP_NODISCARD_EXT inline
4477 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4478 bool
4479 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
4480 {
4481 return _VSTD::binary_search(__first, __last, __value_,
4482 __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
4483 }
4484
4485 // merge
4486
4487 template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
4488 _LIBCPP_CONSTEXPR_AFTER_CXX17
4489 _OutputIterator
4490 __merge(_InputIterator1 __first1, _InputIterator1 __last1,
4491 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
4492 {
4493 for (; __first1 != __last1; ++__result)
4494 {
4495 if (__first2 == __last2)
4496 return _VSTD::copy(__first1, __last1, __result);
4497 if (__comp(*__first2, *__first1))
4498 {
4499 *__result = *__first2;
4500 ++__first2;
4501 }
4502 else
4503 {
4504 *__result = *__first1;
4505 ++__first1;
4506 }
4507 }
4508 return _VSTD::copy(__first2, __last2, __result);
4509 }
4510
4511 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
4512 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4513 _OutputIterator
4514 merge(_InputIterator1 __first1, _InputIterator1 __last1,
4515 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
4516 {
4517 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4518 return _VSTD::__merge<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
4519 }
4520
4521 template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
4522 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4523 _OutputIterator
4524 merge(_InputIterator1 __first1, _InputIterator1 __last1,
4525 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
4526 {
4527 typedef typename iterator_traits<_InputIterator1>::value_type __v1;
4528 typedef typename iterator_traits<_InputIterator2>::value_type __v2;
4529 return _VSTD::merge(__first1, __last1, __first2, __last2, __result, __less<__v1, __v2>());
4530 }
4531
4532 // inplace_merge
4533
4534 template <class _Compare, class _InputIterator1, class _InputIterator2,
4535 class _OutputIterator>
4536 void __half_inplace_merge(_InputIterator1 __first1, _InputIterator1 __last1,
4537 _InputIterator2 __first2, _InputIterator2 __last2,
4538 _OutputIterator __result, _Compare __comp)
4539 {
4540 for (; __first1 != __last1; ++__result)
4541 {
4542 if (__first2 == __last2)
4543 {
4544 _VSTD::move(__first1, __last1, __result);
4545 return;
4546 }
4547
4548 if (__comp(*__first2, *__first1))
4549 {
4550 *__result = _VSTD::move(*__first2);
4551 ++__first2;
4552 }
4553 else
4554 {
4555 *__result = _VSTD::move(*__first1);
4556 ++__first1;
4557 }
4558 }
4559 // __first2 through __last2 are already in the right spot.
4560 }
4561
4562 template <class _Compare, class _BidirectionalIterator>
4563 void
4564 __buffered_inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
4565 _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
4566 typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
4567 typename iterator_traits<_BidirectionalIterator>::value_type* __buff)
4568 {
4569 typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
4570 __destruct_n __d(0);
4571 unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
4572 if (__len1 <= __len2)
4573 {
4574 value_type* __p = __buff;
4575 for (_BidirectionalIterator __i = __first; __i != __middle; __d.template __incr<value_type>(), (void) ++__i, (void) ++__p)
4576 ::new ((void*)__p) value_type(_VSTD::move(*__i));
4577 _VSTD::__half_inplace_merge<_Compare>(__buff, __p, __middle, __last, __first, __comp);
4578 }
4579 else
4580 {
4581 value_type* __p = __buff;
4582 for (_BidirectionalIterator __i = __middle; __i != __last; __d.template __incr<value_type>(), (void) ++__i, (void) ++__p)
4583 ::new ((void*)__p) value_type(_VSTD::move(*__i));
4584 typedef reverse_iterator<_BidirectionalIterator> _RBi;
4585 typedef reverse_iterator<value_type*> _Rv;
4586 typedef __invert<_Compare> _Inverted;
4587 _VSTD::__half_inplace_merge<_Inverted>(_Rv(__p), _Rv(__buff),
4588 _RBi(__middle), _RBi(__first),
4589 _RBi(__last), _Inverted(__comp));
4590 }
4591 }
4592
4593 template <class _Compare, class _BidirectionalIterator>
4594 void
4595 __inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
4596 _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
4597 typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
4598 typename iterator_traits<_BidirectionalIterator>::value_type* __buff, ptrdiff_t __buff_size)
4599 {
4600 typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
4601 while (true)
4602 {
4603 // if __middle == __last, we're done
4604 if (__len2 == 0)
4605 return;
4606 if (__len1 <= __buff_size || __len2 <= __buff_size)
4607 return _VSTD::__buffered_inplace_merge<_Compare>
4608 (__first, __middle, __last, __comp, __len1, __len2, __buff);
4609 // shrink [__first, __middle) as much as possible (with no moves), returning if it shrinks to 0
4610 for (; true; ++__first, (void) --__len1)
4611 {
4612 if (__len1 == 0)
4613 return;
4614 if (__comp(*__middle, *__first))
4615 break;
4616 }
4617 // __first < __middle < __last
4618 // *__first > *__middle
4619 // partition [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last) such that
4620 // all elements in:
4621 // [__first, __m1) <= [__middle, __m2)
4622 // [__middle, __m2) < [__m1, __middle)
4623 // [__m1, __middle) <= [__m2, __last)
4624 // and __m1 or __m2 is in the middle of its range
4625 _BidirectionalIterator __m1; // "median" of [__first, __middle)
4626 _BidirectionalIterator __m2; // "median" of [__middle, __last)
4627 difference_type __len11; // distance(__first, __m1)
4628 difference_type __len21; // distance(__middle, __m2)
4629 // binary search smaller range
4630 if (__len1 < __len2)
4631 { // __len >= 1, __len2 >= 2
4632 __len21 = __len2 / 2;
4633 __m2 = __middle;
4634 _VSTD::advance(__m2, __len21);
4635 __m1 = _VSTD::__upper_bound<_Compare>(__first, __middle, *__m2, __comp);
4636 __len11 = _VSTD::distance(__first, __m1);
4637 }
4638 else
4639 {
4640 if (__len1 == 1)
4641 { // __len1 >= __len2 && __len2 > 0, therefore __len2 == 1
4642 // It is known *__first > *__middle
4643 swap(*__first, *__middle);
4644 return;
4645 }
4646 // __len1 >= 2, __len2 >= 1
4647 __len11 = __len1 / 2;
4648 __m1 = __first;
4649 _VSTD::advance(__m1, __len11);
4650 __m2 = _VSTD::__lower_bound<_Compare>(__middle, __last, *__m1, __comp);
4651 __len21 = _VSTD::distance(__middle, __m2);
4652 }
4653 difference_type __len12 = __len1 - __len11; // distance(__m1, __middle)
4654 difference_type __len22 = __len2 - __len21; // distance(__m2, __last)
4655 // [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last)
4656 // swap middle two partitions
4657 __middle = _VSTD::rotate(__m1, __middle, __m2);
4658 // __len12 and __len21 now have swapped meanings
4659 // merge smaller range with recursive call and larger with tail recursion elimination
4660 if (__len11 + __len21 < __len12 + __len22)
4661 {
4662 _VSTD::__inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
4663 // _VSTD::__inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
4664 __first = __middle;
4665 __middle = __m2;
4666 __len1 = __len12;
4667 __len2 = __len22;
4668 }
4669 else
4670 {
4671 _VSTD::__inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
4672 // _VSTD::__inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
4673 __last = __middle;
4674 __middle = __m1;
4675 __len1 = __len11;
4676 __len2 = __len21;
4677 }
4678 }
4679 }
4680
4681 template <class _BidirectionalIterator, class _Compare>
4682 inline _LIBCPP_INLINE_VISIBILITY
4683 void
4684 inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
4685 _Compare __comp)
4686 {
4687 typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
4688 typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
4689 difference_type __len1 = _VSTD::distance(__first, __middle);
4690 difference_type __len2 = _VSTD::distance(__middle, __last);
4691 difference_type __buf_size = _VSTD::min(__len1, __len2);
4692 pair<value_type*, ptrdiff_t> __buf = _VSTD::get_temporary_buffer<value_type>(__buf_size);
4693 unique_ptr<value_type, __return_temporary_buffer> __h(__buf.first);
4694 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4695 return _VSTD::__inplace_merge<_Comp_ref>(__first, __middle, __last, __comp, __len1, __len2,
4696 __buf.first, __buf.second);
4697 }
4698
4699 template <class _BidirectionalIterator>
4700 inline _LIBCPP_INLINE_VISIBILITY
4701 void
4702 inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last)
4703 {
4704 _VSTD::inplace_merge(__first, __middle, __last,
4705 __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
4706 }
4707
4708 // stable_sort
4709
4710 template <class _Compare, class _InputIterator1, class _InputIterator2>
4711 void
4712 __merge_move_construct(_InputIterator1 __first1, _InputIterator1 __last1,
4713 _InputIterator2 __first2, _InputIterator2 __last2,
4714 typename iterator_traits<_InputIterator1>::value_type* __result, _Compare __comp)
4715 {
4716 typedef typename iterator_traits<_InputIterator1>::value_type value_type;
4717 __destruct_n __d(0);
4718 unique_ptr<value_type, __destruct_n&> __h(__result, __d);
4719 for (; true; ++__result)
4720 {
4721 if (__first1 == __last1)
4722 {
4723 for (; __first2 != __last2; ++__first2, ++__result, (void)__d.template __incr<value_type>())
4724 ::new ((void*)__result) value_type(_VSTD::move(*__first2));
4725 __h.release();
4726 return;
4727 }
4728 if (__first2 == __last2)
4729 {
4730 for (; __first1 != __last1; ++__first1, ++__result, (void)__d.template __incr<value_type>())
4731 ::new ((void*)__result) value_type(_VSTD::move(*__first1));
4732 __h.release();
4733 return;
4734 }
4735 if (__comp(*__first2, *__first1))
4736 {
4737 ::new ((void*)__result) value_type(_VSTD::move(*__first2));
4738 __d.template __incr<value_type>();
4739 ++__first2;
4740 }
4741 else
4742 {
4743 ::new ((void*)__result) value_type(_VSTD::move(*__first1));
4744 __d.template __incr<value_type>();
4745 ++__first1;
4746 }
4747 }
4748 }
4749
4750 template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
4751 void
4752 __merge_move_assign(_InputIterator1 __first1, _InputIterator1 __last1,
4753 _InputIterator2 __first2, _InputIterator2 __last2,
4754 _OutputIterator __result, _Compare __comp)
4755 {
4756 for (; __first1 != __last1; ++__result)
4757 {
4758 if (__first2 == __last2)
4759 {
4760 for (; __first1 != __last1; ++__first1, (void) ++__result)
4761 *__result = _VSTD::move(*__first1);
4762 return;
4763 }
4764 if (__comp(*__first2, *__first1))
4765 {
4766 *__result = _VSTD::move(*__first2);
4767 ++__first2;
4768 }
4769 else
4770 {
4771 *__result = _VSTD::move(*__first1);
4772 ++__first1;
4773 }
4774 }
4775 for (; __first2 != __last2; ++__first2, (void) ++__result)
4776 *__result = _VSTD::move(*__first2);
4777 }
4778
4779 template <class _Compare, class _RandomAccessIterator>
4780 void
4781 __stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
4782 typename iterator_traits<_RandomAccessIterator>::difference_type __len,
4783 typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size);
4784
4785 template <class _Compare, class _RandomAccessIterator>
4786 void
4787 __stable_sort_move(_RandomAccessIterator __first1, _RandomAccessIterator __last1, _Compare __comp,
4788 typename iterator_traits<_RandomAccessIterator>::difference_type __len,
4789 typename iterator_traits<_RandomAccessIterator>::value_type* __first2)
4790 {
4791 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
4792 switch (__len)
4793 {
4794 case 0:
4795 return;
4796 case 1:
4797 ::new ((void*)__first2) value_type(_VSTD::move(*__first1));
4798 return;
4799 case 2:
4800 __destruct_n __d(0);
4801 unique_ptr<value_type, __destruct_n&> __h2(__first2, __d);
4802 if (__comp(*--__last1, *__first1))
4803 {
4804 ::new ((void*)__first2) value_type(_VSTD::move(*__last1));
4805 __d.template __incr<value_type>();
4806 ++__first2;
4807 ::new ((void*)__first2) value_type(_VSTD::move(*__first1));
4808 }
4809 else
4810 {
4811 ::new ((void*)__first2) value_type(_VSTD::move(*__first1));
4812 __d.template __incr<value_type>();
4813 ++__first2;
4814 ::new ((void*)__first2) value_type(_VSTD::move(*__last1));
4815 }
4816 __h2.release();
4817 return;
4818 }
4819 if (__len <= 8)
4820 {
4821 _VSTD::__insertion_sort_move<_Compare>(__first1, __last1, __first2, __comp);
4822 return;
4823 }
4824 typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
4825 _RandomAccessIterator __m = __first1 + __l2;
4826 _VSTD::__stable_sort<_Compare>(__first1, __m, __comp, __l2, __first2, __l2);
4827 _VSTD::__stable_sort<_Compare>(__m, __last1, __comp, __len - __l2, __first2 + __l2, __len - __l2);
4828 _VSTD::__merge_move_construct<_Compare>(__first1, __m, __m, __last1, __first2, __comp);
4829 }
4830
4831 template <class _Tp>
4832 struct __stable_sort_switch
4833 {
4834 static const unsigned value = 128*is_trivially_copy_assignable<_Tp>::value;
4835 };
4836
4837 template <class _Compare, class _RandomAccessIterator>
4838 void
4839 __stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
4840 typename iterator_traits<_RandomAccessIterator>::difference_type __len,
4841 typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size)
4842 {
4843 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
4844 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
4845 switch (__len)
4846 {
4847 case 0:
4848 case 1:
4849 return;
4850 case 2:
4851 if (__comp(*--__last, *__first))
4852 swap(*__first, *__last);
4853 return;
4854 }
4855 if (__len <= static_cast<difference_type>(__stable_sort_switch<value_type>::value))
4856 {
4857 _VSTD::__insertion_sort<_Compare>(__first, __last, __comp);
4858 return;
4859 }
4860 typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
4861 _RandomAccessIterator __m = __first + __l2;
4862 if (__len <= __buff_size)
4863 {
4864 __destruct_n __d(0);
4865 unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
4866 _VSTD::__stable_sort_move<_Compare>(__first, __m, __comp, __l2, __buff);
4867 __d.__set(__l2, (value_type*)nullptr);
4868 _VSTD::__stable_sort_move<_Compare>(__m, __last, __comp, __len - __l2, __buff + __l2);
4869 __d.__set(__len, (value_type*)nullptr);
4870 _VSTD::__merge_move_assign<_Compare>(__buff, __buff + __l2, __buff + __l2, __buff + __len, __first, __comp);
4871 // _VSTD::__merge<_Compare>(move_iterator<value_type*>(__buff),
4872 // move_iterator<value_type*>(__buff + __l2),
4873 // move_iterator<_RandomAccessIterator>(__buff + __l2),
4874 // move_iterator<_RandomAccessIterator>(__buff + __len),
4875 // __first, __comp);
4876 return;
4877 }
4878 _VSTD::__stable_sort<_Compare>(__first, __m, __comp, __l2, __buff, __buff_size);
4879 _VSTD::__stable_sort<_Compare>(__m, __last, __comp, __len - __l2, __buff, __buff_size);
4880 _VSTD::__inplace_merge<_Compare>(__first, __m, __last, __comp, __l2, __len - __l2, __buff, __buff_size);
4881 }
4882
4883 template <class _RandomAccessIterator, class _Compare>
4884 inline _LIBCPP_INLINE_VISIBILITY
4885 void
4886 stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
4887 {
4888 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
4889 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
4890 difference_type __len = __last - __first;
4891 pair<value_type*, ptrdiff_t> __buf(0, 0);
4892 unique_ptr<value_type, __return_temporary_buffer> __h;
4893 if (__len > static_cast<difference_type>(__stable_sort_switch<value_type>::value))
4894 {
4895 __buf = _VSTD::get_temporary_buffer<value_type>(__len);
4896 __h.reset(__buf.first);
4897 }
4898 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4899 _VSTD::__stable_sort<_Comp_ref>(__first, __last, __comp, __len, __buf.first, __buf.second);
4900 }
4901
4902 template <class _RandomAccessIterator>
4903 inline _LIBCPP_INLINE_VISIBILITY
4904 void
4905 stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
4906 {
4907 _VSTD::stable_sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
4908 }
4909
4910 // is_heap_until
4911
4912 template <class _RandomAccessIterator, class _Compare>
4913 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
4914 is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
4915 {
4916 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
4917 difference_type __len = __last - __first;
4918 difference_type __p = 0;
4919 difference_type __c = 1;
4920 _RandomAccessIterator __pp = __first;
4921 while (__c < __len)
4922 {
4923 _RandomAccessIterator __cp = __first + __c;
4924 if (__comp(*__pp, *__cp))
4925 return __cp;
4926 ++__c;
4927 ++__cp;
4928 if (__c == __len)
4929 return __last;
4930 if (__comp(*__pp, *__cp))
4931 return __cp;
4932 ++__p;
4933 ++__pp;
4934 __c = 2 * __p + 1;
4935 }
4936 return __last;
4937 }
4938
4939 template<class _RandomAccessIterator>
4940 _LIBCPP_NODISCARD_EXT inline
4941 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4942 _RandomAccessIterator
4943 is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last)
4944 {
4945 return _VSTD::is_heap_until(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
4946 }
4947
4948 // is_heap
4949
4950 template <class _RandomAccessIterator, class _Compare>
4951 _LIBCPP_NODISCARD_EXT inline
4952 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4953 bool
4954 is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
4955 {
4956 return _VSTD::is_heap_until(__first, __last, __comp) == __last;
4957 }
4958
4959 template<class _RandomAccessIterator>
4960 _LIBCPP_NODISCARD_EXT inline
4961 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4962 bool
4963 is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
4964 {
4965 return _VSTD::is_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
4966 }
4967
4968 // push_heap
4969
4970 template <class _Compare, class _RandomAccessIterator>
4971 _LIBCPP_CONSTEXPR_AFTER_CXX11 void
4972 __sift_up(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
4973 typename iterator_traits<_RandomAccessIterator>::difference_type __len)
4974 {
4975 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
4976 if (__len > 1)
4977 {
4978 __len = (__len - 2) / 2;
4979 _RandomAccessIterator __ptr = __first + __len;
4980 if (__comp(*__ptr, *--__last))
4981 {
4982 value_type __t(_VSTD::move(*__last));
4983 do
4984 {
4985 *__last = _VSTD::move(*__ptr);
4986 __last = __ptr;
4987 if (__len == 0)
4988 break;
4989 __len = (__len - 1) / 2;
4990 __ptr = __first + __len;
4991 } while (__comp(*__ptr, __t));
4992 *__last = _VSTD::move(__t);
4993 }
4994 }
4995 }
4996
4997 template <class _RandomAccessIterator, class _Compare>
4998 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
4999 void
5000 push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
5001 {
5002 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5003 _VSTD::__sift_up<_Comp_ref>(__first, __last, __comp, __last - __first);
5004 }
5005
5006 template <class _RandomAccessIterator>
5007 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5008 void
5009 push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
5010 {
5011 _VSTD::push_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
5012 }
5013
5014 // pop_heap
5015
5016 template <class _Compare, class _RandomAccessIterator>
5017 _LIBCPP_CONSTEXPR_AFTER_CXX11 void
5018 __sift_down(_RandomAccessIterator __first, _RandomAccessIterator /*__last*/,
5019 _Compare __comp,
5020 typename iterator_traits<_RandomAccessIterator>::difference_type __len,
5021 _RandomAccessIterator __start)
5022 {
5023 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
5024 typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
5025 // left-child of __start is at 2 * __start + 1
5026 // right-child of __start is at 2 * __start + 2
5027 difference_type __child = __start - __first;
5028
5029 if (__len < 2 || (__len - 2) / 2 < __child)
5030 return;
5031
5032 __child = 2 * __child + 1;
5033 _RandomAccessIterator __child_i = __first + __child;
5034
5035 if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
5036 // right-child exists and is greater than left-child
5037 ++__child_i;
5038 ++__child;
5039 }
5040
5041 // check if we are in heap-order
5042 if (__comp(*__child_i, *__start))
5043 // we are, __start is larger than it's largest child
5044 return;
5045
5046 value_type __top(_VSTD::move(*__start));
5047 do
5048 {
5049 // we are not in heap-order, swap the parent with its largest child
5050 *__start = _VSTD::move(*__child_i);
5051 __start = __child_i;
5052
5053 if ((__len - 2) / 2 < __child)
5054 break;
5055
5056 // recompute the child based off of the updated parent
5057 __child = 2 * __child + 1;
5058 __child_i = __first + __child;
5059
5060 if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
5061 // right-child exists and is greater than left-child
5062 ++__child_i;
5063 ++__child;
5064 }
5065
5066 // check if we are in heap-order
5067 } while (!__comp(*__child_i, __top));
5068 *__start = _VSTD::move(__top);
5069 }
5070
5071 template <class _Compare, class _RandomAccessIterator>
5072 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5073 void
5074 __pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
5075 typename iterator_traits<_RandomAccessIterator>::difference_type __len)
5076 {
5077 if (__len > 1)
5078 {
5079 swap(*__first, *--__last);
5080 _VSTD::__sift_down<_Compare>(__first, __last, __comp, __len - 1, __first);
5081 }
5082 }
5083
5084 template <class _RandomAccessIterator, class _Compare>
5085 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5086 void
5087 pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
5088 {
5089 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5090 _VSTD::__pop_heap<_Comp_ref>(__first, __last, __comp, __last - __first);
5091 }
5092
5093 template <class _RandomAccessIterator>
5094 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5095 void
5096 pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
5097 {
5098 _VSTD::pop_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
5099 }
5100
5101 // make_heap
5102
5103 template <class _Compare, class _RandomAccessIterator>
5104 _LIBCPP_CONSTEXPR_AFTER_CXX11 void
5105 __make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
5106 {
5107 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
5108 difference_type __n = __last - __first;
5109 if (__n > 1)
5110 {
5111 // start from the first parent, there is no need to consider children
5112 for (difference_type __start = (__n - 2) / 2; __start >= 0; --__start)
5113 {
5114 _VSTD::__sift_down<_Compare>(__first, __last, __comp, __n, __first + __start);
5115 }
5116 }
5117 }
5118
5119 template <class _RandomAccessIterator, class _Compare>
5120 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5121 void
5122 make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
5123 {
5124 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5125 _VSTD::__make_heap<_Comp_ref>(__first, __last, __comp);
5126 }
5127
5128 template <class _RandomAccessIterator>
5129 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5130 void
5131 make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
5132 {
5133 _VSTD::make_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
5134 }
5135
5136 // sort_heap
5137
5138 template <class _Compare, class _RandomAccessIterator>
5139 _LIBCPP_CONSTEXPR_AFTER_CXX17 void
5140 __sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
5141 {
5142 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
5143 for (difference_type __n = __last - __first; __n > 1; --__last, (void) --__n)
5144 _VSTD::__pop_heap<_Compare>(__first, __last, __comp, __n);
5145 }
5146
5147 template <class _RandomAccessIterator, class _Compare>
5148 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5149 void
5150 sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
5151 {
5152 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5153 _VSTD::__sort_heap<_Comp_ref>(__first, __last, __comp);
5154 }
5155
5156 template <class _RandomAccessIterator>
5157 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5158 void
5159 sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
5160 {
5161 _VSTD::sort_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
5162 }
5163
5164 // partial_sort
5165
5166 template <class _Compare, class _RandomAccessIterator>
5167 _LIBCPP_CONSTEXPR_AFTER_CXX17 void
5168 __partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
5169 _Compare __comp)
5170 {
5171 _VSTD::__make_heap<_Compare>(__first, __middle, __comp);
5172 typename iterator_traits<_RandomAccessIterator>::difference_type __len = __middle - __first;
5173 for (_RandomAccessIterator __i = __middle; __i != __last; ++__i)
5174 {
5175 if (__comp(*__i, *__first))
5176 {
5177 swap(*__i, *__first);
5178 _VSTD::__sift_down<_Compare>(__first, __middle, __comp, __len, __first);
5179 }
5180 }
5181 _VSTD::__sort_heap<_Compare>(__first, __middle, __comp);
5182 }
5183
5184 template <class _RandomAccessIterator, class _Compare>
5185 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5186 void
5187 partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
5188 _Compare __comp)
5189 {
5190 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5191 _VSTD::__partial_sort<_Comp_ref>(__first, __middle, __last, __comp);
5192 }
5193
5194 template <class _RandomAccessIterator>
5195 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5196 void
5197 partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
5198 {
5199 _VSTD::partial_sort(__first, __middle, __last,
5200 __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
5201 }
5202
5203 // partial_sort_copy
5204
5205 template <class _Compare, class _InputIterator, class _RandomAccessIterator>
5206 _LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
5207 __partial_sort_copy(_InputIterator __first, _InputIterator __last,
5208 _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
5209 {
5210 _RandomAccessIterator __r = __result_first;
5211 if (__r != __result_last)
5212 {
5213 for (; __first != __last && __r != __result_last; ++__first, (void) ++__r)
5214 *__r = *__first;
5215 _VSTD::__make_heap<_Compare>(__result_first, __r, __comp);
5216 typename iterator_traits<_RandomAccessIterator>::difference_type __len = __r - __result_first;
5217 for (; __first != __last; ++__first)
5218 if (__comp(*__first, *__result_first))
5219 {
5220 *__result_first = *__first;
5221 _VSTD::__sift_down<_Compare>(__result_first, __r, __comp, __len, __result_first);
5222 }
5223 _VSTD::__sort_heap<_Compare>(__result_first, __r, __comp);
5224 }
5225 return __r;
5226 }
5227
5228 template <class _InputIterator, class _RandomAccessIterator, class _Compare>
5229 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5230 _RandomAccessIterator
5231 partial_sort_copy(_InputIterator __first, _InputIterator __last,
5232 _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
5233 {
5234 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5235 return _VSTD::__partial_sort_copy<_Comp_ref>(__first, __last, __result_first, __result_last, __comp);
5236 }
5237
5238 template <class _InputIterator, class _RandomAccessIterator>
5239 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5240 _RandomAccessIterator
5241 partial_sort_copy(_InputIterator __first, _InputIterator __last,
5242 _RandomAccessIterator __result_first, _RandomAccessIterator __result_last)
5243 {
5244 return _VSTD::partial_sort_copy(__first, __last, __result_first, __result_last,
5245 __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
5246 }
5247
5248 // nth_element
5249
5250 template<class _Compare, class _RandomAccessIterator>
5251 _LIBCPP_CONSTEXPR_AFTER_CXX11 bool
5252 __nth_element_find_guard(_RandomAccessIterator& __i, _RandomAccessIterator& __j,
5253 _RandomAccessIterator __m, _Compare __comp)
5254 {
5255 // manually guard downward moving __j against __i
5256 while (true) {
5257 if (__i == --__j) {
5258 return false;
5259 }
5260 if (__comp(*__j, *__m)) {
5261 return true; // found guard for downward moving __j, now use unguarded partition
5262 }
5263 }
5264 }
5265
5266 template <class _Compare, class _RandomAccessIterator>
5267 _LIBCPP_CONSTEXPR_AFTER_CXX11 void
5268 __nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
5269 {
5270 // _Compare is known to be a reference type
5271 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
5272 const difference_type __limit = 7;
5273 while (true)
5274 {
5275 if (__nth == __last)
5276 return;
5277 difference_type __len = __last - __first;
5278 switch (__len)
5279 {
5280 case 0:
5281 case 1:
5282 return;
5283 case 2:
5284 if (__comp(*--__last, *__first))
5285 swap(*__first, *__last);
5286 return;
5287 case 3:
5288 {
5289 _RandomAccessIterator __m = __first;
5290 _VSTD::__sort3<_Compare>(__first, ++__m, --__last, __comp);
5291 return;
5292 }
5293 }
5294 if (__len <= __limit)
5295 {
5296 _VSTD::__selection_sort<_Compare>(__first, __last, __comp);
5297 return;
5298 }
5299 // __len > __limit >= 3
5300 _RandomAccessIterator __m = __first + __len/2;
5301 _RandomAccessIterator __lm1 = __last;
5302 unsigned __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, --__lm1, __comp);
5303 // *__m is median
5304 // partition [__first, __m) < *__m and *__m <= [__m, __last)
5305 // (this inhibits tossing elements equivalent to __m around unnecessarily)
5306 _RandomAccessIterator __i = __first;
5307 _RandomAccessIterator __j = __lm1;
5308 // j points beyond range to be tested, *__lm1 is known to be <= *__m
5309 // The search going up is known to be guarded but the search coming down isn't.
5310 // Prime the downward search with a guard.
5311 if (!__comp(*__i, *__m)) // if *__first == *__m
5312 {
5313 // *__first == *__m, *__first doesn't go in first part
5314 if (_VSTD::__nth_element_find_guard<_Compare>(__i, __j, __m, __comp)) {
5315 swap(*__i, *__j);
5316 ++__n_swaps;
5317 } else {
5318 // *__first == *__m, *__m <= all other elements
5319 // Partition instead into [__first, __i) == *__first and *__first < [__i, __last)
5320 ++__i; // __first + 1
5321 __j = __last;
5322 if (!__comp(*__first, *--__j)) { // we need a guard if *__first == *(__last-1)
5323 while (true) {
5324 if (__i == __j) {
5325 return; // [__first, __last) all equivalent elements
5326 } else if (__comp(*__first, *__i)) {
5327 swap(*__i, *__j);
5328 ++__n_swaps;
5329 ++__i;
5330 break;
5331 }
5332 ++__i;
5333 }
5334 }
5335 // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
5336 if (__i == __j) {
5337 return;
5338 }
5339 while (true) {
5340 while (!__comp(*__first, *__i))
5341 ++__i;
5342 while (__comp(*__first, *--__j))
5343 ;
5344 if (__i >= __j)
5345 break;
5346 swap(*__i, *__j);
5347 ++__n_swaps;
5348 ++__i;
5349 }
5350 // [__first, __i) == *__first and *__first < [__i, __last)
5351 // The first part is sorted,
5352 if (__nth < __i) {
5353 return;
5354 }
5355 // __nth_element the second part
5356 // _VSTD::__nth_element<_Compare>(__i, __nth, __last, __comp);
5357 __first = __i;
5358 continue;
5359 }
5360 }
5361 ++__i;
5362 // j points beyond range to be tested, *__lm1 is known to be <= *__m
5363 // if not yet partitioned...
5364 if (__i < __j)
5365 {
5366 // known that *(__i - 1) < *__m
5367 while (true)
5368 {
5369 // __m still guards upward moving __i
5370 while (__comp(*__i, *__m))
5371 ++__i;
5372 // It is now known that a guard exists for downward moving __j
5373 while (!__comp(*--__j, *__m))
5374 ;
5375 if (__i >= __j)
5376 break;
5377 swap(*__i, *__j);
5378 ++__n_swaps;
5379 // It is known that __m != __j
5380 // If __m just moved, follow it
5381 if (__m == __i)
5382 __m = __j;
5383 ++__i;
5384 }
5385 }
5386 // [__first, __i) < *__m and *__m <= [__i, __last)
5387 if (__i != __m && __comp(*__m, *__i))
5388 {
5389 swap(*__i, *__m);
5390 ++__n_swaps;
5391 }
5392 // [__first, __i) < *__i and *__i <= [__i+1, __last)
5393 if (__nth == __i)
5394 return;
5395 if (__n_swaps == 0)
5396 {
5397 // We were given a perfectly partitioned sequence. Coincidence?
5398 if (__nth < __i)
5399 {
5400 // Check for [__first, __i) already sorted
5401 __j = __m = __first;
5402 while (true) {
5403 if (++__j == __i) {
5404 // [__first, __i) sorted
5405 return;
5406 }
5407 if (__comp(*__j, *__m)) {
5408 // not yet sorted, so sort
5409 break;
5410 }
5411 __m = __j;
5412 }
5413 }
5414 else
5415 {
5416 // Check for [__i, __last) already sorted
5417 __j = __m = __i;
5418 while (true) {
5419 if (++__j == __last) {
5420 // [__i, __last) sorted
5421 return;
5422 }
5423 if (__comp(*__j, *__m)) {
5424 // not yet sorted, so sort
5425 break;
5426 }
5427 __m = __j;
5428 }
5429 }
5430 }
5431 // __nth_element on range containing __nth
5432 if (__nth < __i)
5433 {
5434 // _VSTD::__nth_element<_Compare>(__first, __nth, __i, __comp);
5435 __last = __i;
5436 }
5437 else
5438 {
5439 // _VSTD::__nth_element<_Compare>(__i+1, __nth, __last, __comp);
5440 __first = ++__i;
5441 }
5442 }
5443 }
5444
5445 template <class _RandomAccessIterator, class _Compare>
5446 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5447 void
5448 nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
5449 {
5450 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5451 _VSTD::__nth_element<_Comp_ref>(__first, __nth, __last, __comp);
5452 }
5453
5454 template <class _RandomAccessIterator>
5455 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5456 void
5457 nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last)
5458 {
5459 _VSTD::nth_element(__first, __nth, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
5460 }
5461
5462 // sort
5463
5464 template <class _RandomAccessIterator, class _Compare>
5465 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5466 void
5467 sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
5468 {
5469 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5470 if (__libcpp_is_constant_evaluated()) {
5471 _VSTD::__partial_sort<_Comp_ref>(__first, __last, __last, _Comp_ref(__comp));
5472 } else {
5473 _VSTD::__sort<_Comp_ref>(_VSTD::__unwrap_iter(__first), _VSTD::__unwrap_iter(__last), _Comp_ref(__comp));
5474 }
5475 }
5476
5477 template <class _RandomAccessIterator>
5478 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5479 void
5480 sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
5481 {
5482 _VSTD::sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
5483 }
5484
5485 // includes
5486
5487 template <class _Compare, class _InputIterator1, class _InputIterator2>
5488 _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
5489 __includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
5490 _Compare __comp)
5491 {
5492 for (; __first2 != __last2; ++__first1)
5493 {
5494 if (__first1 == __last1 || __comp(*__first2, *__first1))
5495 return false;
5496 if (!__comp(*__first1, *__first2))
5497 ++__first2;
5498 }
5499 return true;
5500 }
5501
5502 template <class _InputIterator1, class _InputIterator2, class _Compare>
5503 _LIBCPP_NODISCARD_EXT inline
5504 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5505 bool
5506 includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
5507 _Compare __comp)
5508 {
5509 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5510 return _VSTD::__includes<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
5511 }
5512
5513 template <class _InputIterator1, class _InputIterator2>
5514 _LIBCPP_NODISCARD_EXT inline
5515 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5516 bool
5517 includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2)
5518 {
5519 return _VSTD::includes(__first1, __last1, __first2, __last2,
5520 __less<typename iterator_traits<_InputIterator1>::value_type,
5521 typename iterator_traits<_InputIterator2>::value_type>());
5522 }
5523
5524 // set_union
5525
5526 template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
5527 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
5528 __set_union(_InputIterator1 __first1, _InputIterator1 __last1,
5529 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
5530 {
5531 for (; __first1 != __last1; ++__result)
5532 {
5533 if (__first2 == __last2)
5534 return _VSTD::copy(__first1, __last1, __result);
5535 if (__comp(*__first2, *__first1))
5536 {
5537 *__result = *__first2;
5538 ++__first2;
5539 }
5540 else
5541 {
5542 if (!__comp(*__first1, *__first2))
5543 ++__first2;
5544 *__result = *__first1;
5545 ++__first1;
5546 }
5547 }
5548 return _VSTD::copy(__first2, __last2, __result);
5549 }
5550
5551 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
5552 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5553 _OutputIterator
5554 set_union(_InputIterator1 __first1, _InputIterator1 __last1,
5555 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
5556 {
5557 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5558 return _VSTD::__set_union<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
5559 }
5560
5561 template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
5562 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5563 _OutputIterator
5564 set_union(_InputIterator1 __first1, _InputIterator1 __last1,
5565 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
5566 {
5567 return _VSTD::set_union(__first1, __last1, __first2, __last2, __result,
5568 __less<typename iterator_traits<_InputIterator1>::value_type,
5569 typename iterator_traits<_InputIterator2>::value_type>());
5570 }
5571
5572 // set_intersection
5573
5574 template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
5575 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
5576 __set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
5577 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
5578 {
5579 while (__first1 != __last1 && __first2 != __last2)
5580 {
5581 if (__comp(*__first1, *__first2))
5582 ++__first1;
5583 else
5584 {
5585 if (!__comp(*__first2, *__first1))
5586 {
5587 *__result = *__first1;
5588 ++__result;
5589 ++__first1;
5590 }
5591 ++__first2;
5592 }
5593 }
5594 return __result;
5595 }
5596
5597 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
5598 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5599 _OutputIterator
5600 set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
5601 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
5602 {
5603 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5604 return _VSTD::__set_intersection<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
5605 }
5606
5607 template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
5608 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5609 _OutputIterator
5610 set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
5611 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
5612 {
5613 return _VSTD::set_intersection(__first1, __last1, __first2, __last2, __result,
5614 __less<typename iterator_traits<_InputIterator1>::value_type,
5615 typename iterator_traits<_InputIterator2>::value_type>());
5616 }
5617
5618 // set_difference
5619
5620 template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
5621 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
5622 __set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5623 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
5624 {
5625 while (__first1 != __last1)
5626 {
5627 if (__first2 == __last2)
5628 return _VSTD::copy(__first1, __last1, __result);
5629 if (__comp(*__first1, *__first2))
5630 {
5631 *__result = *__first1;
5632 ++__result;
5633 ++__first1;
5634 }
5635 else
5636 {
5637 if (!__comp(*__first2, *__first1))
5638 ++__first1;
5639 ++__first2;
5640 }
5641 }
5642 return __result;
5643 }
5644
5645 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
5646 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5647 _OutputIterator
5648 set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5649 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
5650 {
5651 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5652 return _VSTD::__set_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
5653 }
5654
5655 template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
5656 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5657 _OutputIterator
5658 set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5659 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
5660 {
5661 return _VSTD::set_difference(__first1, __last1, __first2, __last2, __result,
5662 __less<typename iterator_traits<_InputIterator1>::value_type,
5663 typename iterator_traits<_InputIterator2>::value_type>());
5664 }
5665
5666 // set_symmetric_difference
5667
5668 template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
5669 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
5670 __set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5671 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
5672 {
5673 while (__first1 != __last1)
5674 {
5675 if (__first2 == __last2)
5676 return _VSTD::copy(__first1, __last1, __result);
5677 if (__comp(*__first1, *__first2))
5678 {
5679 *__result = *__first1;
5680 ++__result;
5681 ++__first1;
5682 }
5683 else
5684 {
5685 if (__comp(*__first2, *__first1))
5686 {
5687 *__result = *__first2;
5688 ++__result;
5689 }
5690 else
5691 ++__first1;
5692 ++__first2;
5693 }
5694 }
5695 return _VSTD::copy(__first2, __last2, __result);
5696 }
5697
5698 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
5699 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5700 _OutputIterator
5701 set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5702 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
5703 {
5704 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5705 return _VSTD::__set_symmetric_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
5706 }
5707
5708 template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
5709 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5710 _OutputIterator
5711 set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5712 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
5713 {
5714 return _VSTD::set_symmetric_difference(__first1, __last1, __first2, __last2, __result,
5715 __less<typename iterator_traits<_InputIterator1>::value_type,
5716 typename iterator_traits<_InputIterator2>::value_type>());
5717 }
5718
5719 // lexicographical_compare
5720
5721 template <class _Compare, class _InputIterator1, class _InputIterator2>
5722 _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
5723 __lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
5724 _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
5725 {
5726 for (; __first2 != __last2; ++__first1, (void) ++__first2)
5727 {
5728 if (__first1 == __last1 || __comp(*__first1, *__first2))
5729 return true;
5730 if (__comp(*__first2, *__first1))
5731 return false;
5732 }
5733 return false;
5734 }
5735
5736 template <class _InputIterator1, class _InputIterator2, class _Compare>
5737 _LIBCPP_NODISCARD_EXT inline
5738 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5739 bool
5740 lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
5741 _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
5742 {
5743 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5744 return _VSTD::__lexicographical_compare<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
5745 }
5746
5747 template <class _InputIterator1, class _InputIterator2>
5748 _LIBCPP_NODISCARD_EXT inline
5749 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5750 bool
5751 lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
5752 _InputIterator2 __first2, _InputIterator2 __last2)
5753 {
5754 return _VSTD::lexicographical_compare(__first1, __last1, __first2, __last2,
5755 __less<typename iterator_traits<_InputIterator1>::value_type,
5756 typename iterator_traits<_InputIterator2>::value_type>());
5757 }
5758
5759 // next_permutation
5760
5761 template <class _Compare, class _BidirectionalIterator>
5762 _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
5763 __next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
5764 {
5765 _BidirectionalIterator __i = __last;
5766 if (__first == __last || __first == --__i)
5767 return false;
5768 while (true)
5769 {
5770 _BidirectionalIterator __ip1 = __i;
5771 if (__comp(*--__i, *__ip1))
5772 {
5773 _BidirectionalIterator __j = __last;
5774 while (!__comp(*__i, *--__j))
5775 ;
5776 swap(*__i, *__j);
5777 _VSTD::reverse(__ip1, __last);
5778 return true;
5779 }
5780 if (__i == __first)
5781 {
5782 _VSTD::reverse(__first, __last);
5783 return false;
5784 }
5785 }
5786 }
5787
5788 template <class _BidirectionalIterator, class _Compare>
5789 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5790 bool
5791 next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
5792 {
5793 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5794 return _VSTD::__next_permutation<_Comp_ref>(__first, __last, __comp);
5795 }
5796
5797 template <class _BidirectionalIterator>
5798 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5799 bool
5800 next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
5801 {
5802 return _VSTD::next_permutation(__first, __last,
5803 __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
5804 }
5805
5806 // prev_permutation
5807
5808 template <class _Compare, class _BidirectionalIterator>
5809 _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
5810 __prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
5811 {
5812 _BidirectionalIterator __i = __last;
5813 if (__first == __last || __first == --__i)
5814 return false;
5815 while (true)
5816 {
5817 _BidirectionalIterator __ip1 = __i;
5818 if (__comp(*__ip1, *--__i))
5819 {
5820 _BidirectionalIterator __j = __last;
5821 while (!__comp(*--__j, *__i))
5822 ;
5823 swap(*__i, *__j);
5824 _VSTD::reverse(__ip1, __last);
5825 return true;
5826 }
5827 if (__i == __first)
5828 {
5829 _VSTD::reverse(__first, __last);
5830 return false;
5831 }
5832 }
5833 }
5834
5835 template <class _BidirectionalIterator, class _Compare>
5836 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5837 bool
5838 prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
5839 {
5840 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
5841 return _VSTD::__prev_permutation<_Comp_ref>(__first, __last, __comp);
5842 }
5843
5844 template <class _BidirectionalIterator>
5845 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
5846 bool
5847 prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
5848 {
5849 return _VSTD::prev_permutation(__first, __last,
5850 __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
5851 }
5852
5853 _LIBCPP_END_NAMESPACE_STD
5854
5855 _LIBCPP_POP_MACROS
5856
5857 #if defined(_LIBCPP_HAS_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
5858 # include <__pstl_algorithm>
5859 #endif
5860
5861 #endif // _LIBCPP_ALGORITHM
5862