1 /* A Fibonacci heap datatype. 2 Copyright (C) 1998-2016 Free Software Foundation, Inc. 3 Contributed by Daniel Berlin (dan@cgsoftware.com). 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it 8 under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2, or (at your option) 10 any later version. 11 12 GCC is distributed in the hope that it will be useful, but 13 WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING. If not, write to 19 the Free Software Foundation, 51 Franklin Street - Fifth Floor, 20 Boston, MA 02110-1301, USA. */ 21 22 /* Fibonacci heaps are somewhat complex, but, there's an article in 23 DDJ that explains them pretty well: 24 25 http://www.ddj.com/articles/1997/9701/9701o/9701o.htm?topic=algoritms 26 27 Introduction to algorithms by Corman and Rivest also goes over them. 28 29 The original paper that introduced them is "Fibonacci heaps and their 30 uses in improved network optimization algorithms" by Tarjan and 31 Fredman (JACM 34(3), July 1987). 32 33 Amortized and real worst case time for operations: 34 35 ExtractMin: O(lg n) amortized. O(n) worst case. 36 DecreaseKey: O(1) amortized. O(lg n) worst case. 37 Insert: O(2) amortized. O(1) actual. 38 Union: O(1) amortized. O(1) actual. */ 39 40 #ifndef _FIBHEAP_H_ 41 #define _FIBHEAP_H_ 42 43 #include "ansidecl.h" 44 45 #ifdef __cplusplus 46 extern "C" { 47 #endif 48 49 typedef long fibheapkey_t; 50 51 typedef struct fibheap 52 { 53 size_t nodes; 54 struct fibnode *min; 55 struct fibnode *root; 56 } *fibheap_t; 57 58 typedef struct fibnode 59 { 60 struct fibnode *parent; 61 struct fibnode *child; 62 struct fibnode *left; 63 struct fibnode *right; 64 fibheapkey_t key; 65 void *data; 66 #if defined (__GNUC__) && (!defined (SIZEOF_INT) || SIZEOF_INT < 4) 67 __extension__ unsigned long int degree : 31; 68 __extension__ unsigned long int mark : 1; 69 #else 70 unsigned int degree : 31; 71 unsigned int mark : 1; 72 #endif 73 } *fibnode_t; 74 75 extern fibheap_t fibheap_new (void); 76 extern fibnode_t fibheap_insert (fibheap_t, fibheapkey_t, void *); 77 extern int fibheap_empty (fibheap_t); 78 extern fibheapkey_t fibheap_min_key (fibheap_t); 79 extern fibheapkey_t fibheap_replace_key (fibheap_t, fibnode_t, 80 fibheapkey_t); 81 extern void *fibheap_replace_key_data (fibheap_t, fibnode_t, 82 fibheapkey_t, void *); 83 extern void *fibheap_extract_min (fibheap_t); 84 extern void *fibheap_min (fibheap_t); 85 extern void *fibheap_replace_data (fibheap_t, fibnode_t, void *); 86 extern void *fibheap_delete_node (fibheap_t, fibnode_t); 87 extern void fibheap_delete (fibheap_t); 88 extern fibheap_t fibheap_union (fibheap_t, fibheap_t); 89 90 #ifdef __cplusplus 91 } 92 #endif 93 94 #endif /* _FIBHEAP_H_ */ 95