xref: /dflybsd-src/contrib/binutils-2.27/include/fibheap.h (revision e656dc90e3d65d744d534af2f5ea88cf8101ebcf)
1*a9fa9459Szrj /* A Fibonacci heap datatype.
2*a9fa9459Szrj    Copyright (C) 1998-2016 Free Software Foundation, Inc.
3*a9fa9459Szrj    Contributed by Daniel Berlin (dan@cgsoftware.com).
4*a9fa9459Szrj 
5*a9fa9459Szrj This file is part of GCC.
6*a9fa9459Szrj 
7*a9fa9459Szrj GCC is free software; you can redistribute it and/or modify it
8*a9fa9459Szrj under the terms of the GNU General Public License as published by
9*a9fa9459Szrj the Free Software Foundation; either version 2, or (at your option)
10*a9fa9459Szrj any later version.
11*a9fa9459Szrj 
12*a9fa9459Szrj GCC is distributed in the hope that it will be useful, but
13*a9fa9459Szrj WITHOUT ANY WARRANTY; without even the implied warranty of
14*a9fa9459Szrj MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15*a9fa9459Szrj General Public License for more details.
16*a9fa9459Szrj 
17*a9fa9459Szrj You should have received a copy of the GNU General Public License
18*a9fa9459Szrj along with GCC; see the file COPYING.  If not, write to
19*a9fa9459Szrj the Free Software Foundation, 51 Franklin Street - Fifth Floor,
20*a9fa9459Szrj Boston, MA 02110-1301, USA.  */
21*a9fa9459Szrj 
22*a9fa9459Szrj /* Fibonacci heaps are somewhat complex, but, there's an article in
23*a9fa9459Szrj    DDJ that explains them pretty well:
24*a9fa9459Szrj 
25*a9fa9459Szrj    http://www.ddj.com/articles/1997/9701/9701o/9701o.htm?topic=algoritms
26*a9fa9459Szrj 
27*a9fa9459Szrj    Introduction to algorithms by Corman and Rivest also goes over them.
28*a9fa9459Szrj 
29*a9fa9459Szrj    The original paper that introduced them is "Fibonacci heaps and their
30*a9fa9459Szrj    uses in improved network optimization algorithms" by Tarjan and
31*a9fa9459Szrj    Fredman (JACM 34(3), July 1987).
32*a9fa9459Szrj 
33*a9fa9459Szrj    Amortized and real worst case time for operations:
34*a9fa9459Szrj 
35*a9fa9459Szrj    ExtractMin: O(lg n) amortized. O(n) worst case.
36*a9fa9459Szrj    DecreaseKey: O(1) amortized.  O(lg n) worst case.
37*a9fa9459Szrj    Insert: O(2) amortized. O(1) actual.
38*a9fa9459Szrj    Union: O(1) amortized. O(1) actual.  */
39*a9fa9459Szrj 
40*a9fa9459Szrj #ifndef _FIBHEAP_H_
41*a9fa9459Szrj #define _FIBHEAP_H_
42*a9fa9459Szrj 
43*a9fa9459Szrj #include "ansidecl.h"
44*a9fa9459Szrj 
45*a9fa9459Szrj #ifdef __cplusplus
46*a9fa9459Szrj extern "C" {
47*a9fa9459Szrj #endif
48*a9fa9459Szrj 
49*a9fa9459Szrj typedef long fibheapkey_t;
50*a9fa9459Szrj 
51*a9fa9459Szrj typedef struct fibheap
52*a9fa9459Szrj {
53*a9fa9459Szrj   size_t nodes;
54*a9fa9459Szrj   struct fibnode *min;
55*a9fa9459Szrj   struct fibnode *root;
56*a9fa9459Szrj } *fibheap_t;
57*a9fa9459Szrj 
58*a9fa9459Szrj typedef struct fibnode
59*a9fa9459Szrj {
60*a9fa9459Szrj   struct fibnode *parent;
61*a9fa9459Szrj   struct fibnode *child;
62*a9fa9459Szrj   struct fibnode *left;
63*a9fa9459Szrj   struct fibnode *right;
64*a9fa9459Szrj   fibheapkey_t key;
65*a9fa9459Szrj   void *data;
66*a9fa9459Szrj #if defined (__GNUC__) && (!defined (SIZEOF_INT) || SIZEOF_INT < 4)
67*a9fa9459Szrj   __extension__ unsigned long int degree : 31;
68*a9fa9459Szrj   __extension__ unsigned long int mark : 1;
69*a9fa9459Szrj #else
70*a9fa9459Szrj   unsigned int degree : 31;
71*a9fa9459Szrj   unsigned int mark : 1;
72*a9fa9459Szrj #endif
73*a9fa9459Szrj } *fibnode_t;
74*a9fa9459Szrj 
75*a9fa9459Szrj extern fibheap_t fibheap_new (void);
76*a9fa9459Szrj extern fibnode_t fibheap_insert (fibheap_t, fibheapkey_t, void *);
77*a9fa9459Szrj extern int fibheap_empty (fibheap_t);
78*a9fa9459Szrj extern fibheapkey_t fibheap_min_key (fibheap_t);
79*a9fa9459Szrj extern fibheapkey_t fibheap_replace_key (fibheap_t, fibnode_t,
80*a9fa9459Szrj                                          fibheapkey_t);
81*a9fa9459Szrj extern void *fibheap_replace_key_data (fibheap_t, fibnode_t,
82*a9fa9459Szrj                                        fibheapkey_t, void *);
83*a9fa9459Szrj extern void *fibheap_extract_min (fibheap_t);
84*a9fa9459Szrj extern void *fibheap_min (fibheap_t);
85*a9fa9459Szrj extern void *fibheap_replace_data (fibheap_t, fibnode_t, void *);
86*a9fa9459Szrj extern void *fibheap_delete_node (fibheap_t, fibnode_t);
87*a9fa9459Szrj extern void fibheap_delete (fibheap_t);
88*a9fa9459Szrj extern fibheap_t fibheap_union (fibheap_t, fibheap_t);
89*a9fa9459Szrj 
90*a9fa9459Szrj #ifdef __cplusplus
91*a9fa9459Szrj }
92*a9fa9459Szrj #endif
93*a9fa9459Szrj 
94*a9fa9459Szrj #endif /* _FIBHEAP_H_ */
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