1/*
2 * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
3 * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice including the dates of first publication and
13 * either this permission notice or a reference to
14 * http://oss.sgi.com/projects/FreeB/
15 * shall be included in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
21 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
22 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23 * SOFTWARE.
24 *
25 * Except as contained in this notice, the name of Silicon Graphics, Inc.
26 * shall not be used in advertising or otherwise to promote the sale, use or
27 * other dealings in this Software without prior written authorization from
28 * Silicon Graphics, Inc.
29 */
30/*
31** Author: Eric Veach, July 1994.
32**
33*/
34
35#ifndef __priorityq_sort_h_
36#define __priorityq_sort_h_
37
38#include "priorityq-heap.h"
39
40#undef PQkey
41#undef PQhandle
42#undef PriorityQ
43#undef pqNewPriorityQ
44#undef pqDeletePriorityQ
45#undef pqInit
46#undef pqInsert
47#undef pqMinimum
48#undef pqExtractMin
49#undef pqDelete
50#undef pqIsEmpty
51
52/* Use #define's so that another heap implementation can use this one */
53
54#define PQkey			PQSortKey
55#define PQhandle		PQSortHandle
56#define PriorityQ		PriorityQSort
57
58#define pqNewPriorityQ(leq)	__gl_pqSortNewPriorityQ(leq)
59#define pqDeletePriorityQ(pq)	__gl_pqSortDeletePriorityQ(pq)
60
61/* The basic operations are insertion of a new key (pqInsert),
62 * and examination/extraction of a key whose value is minimum
63 * (pqMinimum/pqExtractMin).  Deletion is also allowed (pqDelete);
64 * for this purpose pqInsert returns a "handle" which is supplied
65 * as the argument.
66 *
67 * An initial heap may be created efficiently by calling pqInsert
68 * repeatedly, then calling pqInit.  In any case pqInit must be called
69 * before any operations other than pqInsert are used.
70 *
71 * If the heap is empty, pqMinimum/pqExtractMin will return a NULL key.
72 * This may also be tested with pqIsEmpty.
73 */
74#define pqInit(pq)		__gl_pqSortInit(pq)
75#define pqInsert(pq,key)	__gl_pqSortInsert(pq,key)
76#define pqMinimum(pq)		__gl_pqSortMinimum(pq)
77#define pqExtractMin(pq)	__gl_pqSortExtractMin(pq)
78#define pqDelete(pq,handle)	__gl_pqSortDelete(pq,handle)
79#define pqIsEmpty(pq)		__gl_pqSortIsEmpty(pq)
80
81
82/* Since we support deletion the data structure is a little more
83 * complicated than an ordinary heap.  "nodes" is the heap itself;
84 * active nodes are stored in the range 1..pq->size.  When the
85 * heap exceeds its allocated size (pq->max), its size doubles.
86 * The children of node i are nodes 2i and 2i+1.
87 *
88 * Each node stores an index into an array "handles".  Each handle
89 * stores a key, plus a pointer back to the node which currently
90 * represents that key (ie. nodes[handles[i].node].handle == i).
91 */
92
93typedef PQHeapKey PQkey;
94typedef PQHeapHandle PQhandle;
95typedef struct PriorityQ PriorityQ;
96
97struct PriorityQ {
98  PriorityQHeap	*heap;
99  PQkey		*keys;
100  PQkey		**order;
101  PQhandle	size, max;
102  int		initialized;
103  int		(*leq)(PQkey key1, PQkey key2);
104};
105
106PriorityQ	*pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) );
107void		pqDeletePriorityQ( PriorityQ *pq );
108
109int		pqInit( PriorityQ *pq );
110PQhandle	pqInsert( PriorityQ *pq, PQkey key );
111PQkey		pqExtractMin( PriorityQ *pq );
112void		pqDelete( PriorityQ *pq, PQhandle handle );
113
114PQkey		pqMinimum( PriorityQ *pq );
115int		pqIsEmpty( PriorityQ *pq );
116
117#endif
118