| /* A Fibonacci heap datatype. |
| Copyright (C) 1998-2024 Free Software Foundation, Inc. |
| Contributed by Daniel Berlin (dan@cgsoftware.com). |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it |
| under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GCC is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING. If not, write to |
| the Free Software Foundation, 51 Franklin Street - Fifth Floor, |
| Boston, MA 02110-1301, USA. */ |
| |
| /* Fibonacci heaps are somewhat complex, but, there's an article in |
| DDJ that explains them pretty well: |
| |
| http://www.ddj.com/articles/1997/9701/9701o/9701o.htm?topic=algoritms |
| |
| Introduction to algorithms by Corman and Rivest also goes over them. |
| |
| The original paper that introduced them is "Fibonacci heaps and their |
| uses in improved network optimization algorithms" by Tarjan and |
| Fredman (JACM 34(3), July 1987). |
| |
| Amortized and real worst case time for operations: |
| |
| ExtractMin: O(lg n) amortized. O(n) worst case. |
| DecreaseKey: O(1) amortized. O(lg n) worst case. |
| Insert: O(2) amortized. O(1) actual. |
| Union: O(1) amortized. O(1) actual. */ |
| |
| #ifndef _FIBHEAP_H_ |
| #define _FIBHEAP_H_ |
| |
| #include "ansidecl.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| typedef long fibheapkey_t; |
| |
| typedef struct fibheap |
| { |
| size_t nodes; |
| struct fibnode *min; |
| struct fibnode *root; |
| } *fibheap_t; |
| |
| typedef struct fibnode |
| { |
| struct fibnode *parent; |
| struct fibnode *child; |
| struct fibnode *left; |
| struct fibnode *right; |
| fibheapkey_t key; |
| void *data; |
| #if defined (__GNUC__) && (!defined (SIZEOF_INT) || SIZEOF_INT < 4) |
| __extension__ unsigned long int degree : 31; |
| __extension__ unsigned long int mark : 1; |
| #else |
| unsigned int degree : 31; |
| unsigned int mark : 1; |
| #endif |
| } *fibnode_t; |
| |
| extern fibheap_t fibheap_new (void); |
| extern fibnode_t fibheap_insert (fibheap_t, fibheapkey_t, void *); |
| extern int fibheap_empty (fibheap_t); |
| extern fibheapkey_t fibheap_min_key (fibheap_t); |
| extern fibheapkey_t fibheap_replace_key (fibheap_t, fibnode_t, |
| fibheapkey_t); |
| extern void *fibheap_replace_key_data (fibheap_t, fibnode_t, |
| fibheapkey_t, void *); |
| extern void *fibheap_extract_min (fibheap_t); |
| extern void *fibheap_min (fibheap_t); |
| extern void *fibheap_replace_data (fibheap_t, fibnode_t, void *); |
| extern void *fibheap_delete_node (fibheap_t, fibnode_t); |
| extern void fibheap_delete (fibheap_t); |
| extern fibheap_t fibheap_union (fibheap_t, fibheap_t); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* _FIBHEAP_H_ */ |