fibheap.h revision 1.7
1/* A Fibonacci heap datatype. 2 Copyright (C) 1998-2020 Free Software Foundation, Inc. 3 Contributed by Daniel Berlin (dan@cgsoftware.com). 4 5This file is part of GCC. 6 7GCC is free software; you can redistribute it and/or modify it 8under the terms of the GNU General Public License as published by 9the Free Software Foundation; either version 2, or (at your option) 10any later version. 11 12GCC is distributed in the hope that it will be useful, but 13WITHOUT ANY WARRANTY; without even the implied warranty of 14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15General Public License for more details. 16 17You should have received a copy of the GNU General Public License 18along with GCC; see the file COPYING. If not, write to 19the Free Software Foundation, 51 Franklin Street - Fifth Floor, 20Boston, 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 46extern "C" { 47#endif 48 49typedef long fibheapkey_t; 50 51typedef struct fibheap 52{ 53 size_t nodes; 54 struct fibnode *min; 55 struct fibnode *root; 56} *fibheap_t; 57 58typedef 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 75extern fibheap_t fibheap_new (void); 76extern fibnode_t fibheap_insert (fibheap_t, fibheapkey_t, void *); 77extern int fibheap_empty (fibheap_t); 78extern fibheapkey_t fibheap_min_key (fibheap_t); 79extern fibheapkey_t fibheap_replace_key (fibheap_t, fibnode_t, 80 fibheapkey_t); 81extern void *fibheap_replace_key_data (fibheap_t, fibnode_t, 82 fibheapkey_t, void *); 83extern void *fibheap_extract_min (fibheap_t); 84extern void *fibheap_min (fibheap_t); 85extern void *fibheap_replace_data (fibheap_t, fibnode_t, void *); 86extern void *fibheap_delete_node (fibheap_t, fibnode_t); 87extern void fibheap_delete (fibheap_t); 88extern fibheap_t fibheap_union (fibheap_t, fibheap_t); 89 90#ifdef __cplusplus 91} 92#endif 93 94#endif /* _FIBHEAP_H_ */ 95