1 /* A Fibonacci heap datatype. 2 Copyright 1998, 1999, 2000, 2001, 2002 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, 59 Temple Place - Suite 330, 20 Boston, MA 02111-1307, 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 typedef long fibheapkey_t; 46 47 typedef struct fibheap 48 { 49 size_t nodes; 50 struct fibnode *min; 51 struct fibnode *root; 52 } *fibheap_t; 53 54 typedef struct fibnode 55 { 56 struct fibnode *parent; 57 struct fibnode *child; 58 struct fibnode *left; 59 struct fibnode *right; 60 fibheapkey_t key; 61 void *data; 62 #ifdef __GNUC__ 63 __extension__ unsigned long int degree : 31; 64 __extension__ unsigned long int mark : 1; 65 #else 66 unsigned int degree : 31; 67 unsigned int mark : 1; 68 #endif 69 } *fibnode_t; 70 71 extern fibheap_t fibheap_new PARAMS ((void)); 72 extern fibnode_t fibheap_insert PARAMS ((fibheap_t, fibheapkey_t, void *)); 73 extern int fibheap_empty PARAMS ((fibheap_t)); 74 extern fibheapkey_t fibheap_min_key PARAMS ((fibheap_t)); 75 extern fibheapkey_t fibheap_replace_key PARAMS ((fibheap_t, fibnode_t, 76 fibheapkey_t)); 77 extern void *fibheap_replace_key_data PARAMS ((fibheap_t, fibnode_t, 78 fibheapkey_t, void *)); 79 extern void *fibheap_extract_min PARAMS ((fibheap_t)); 80 extern void *fibheap_min PARAMS ((fibheap_t)); 81 extern void *fibheap_replace_data PARAMS ((fibheap_t, fibnode_t, void *)); 82 extern void *fibheap_delete_node PARAMS ((fibheap_t, fibnode_t)); 83 extern void fibheap_delete PARAMS ((fibheap_t)); 84 extern fibheap_t fibheap_union PARAMS ((fibheap_t, fibheap_t)); 85 86 #endif /* _FIBHEAP_H_ */ 87