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/* A Fibonacci heap datatype. |
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Copyright (C) 1998-2021 Free Software Foundation, Inc. |
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Contributed by Daniel Berlin (dan@cgsoftware.com). |
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|
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This file is part of GCC. |
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|
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GCC is free software; you can redistribute it and/or modify it |
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under the terms of the GNU General Public License as published by |
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the Free Software Foundation; either version 2, or (at your option) |
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any later version. |
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|
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GCC is distributed in the hope that it will be useful, but |
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WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with GCC; see the file COPYING. If not, write to |
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the Free Software Foundation, 51 Franklin Street - Fifth Floor, |
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Boston, MA 02110-1301, USA. */ |
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|
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/* Fibonacci heaps are somewhat complex, but, there's an article in |
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DDJ that explains them pretty well: |
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|
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http://www.ddj.com/articles/1997/9701/9701o/9701o.htm?topic=algoritms |
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|
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Introduction to algorithms by Corman and Rivest also goes over them. |
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|
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The original paper that introduced them is "Fibonacci heaps and their |
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uses in improved network optimization algorithms" by Tarjan and |
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Fredman (JACM 34(3), July 1987). |
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|
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Amortized and real worst case time for operations: |
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|
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ExtractMin: O(lg n) amortized. O(n) worst case. |
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DecreaseKey: O(1) amortized. O(lg n) worst case. |
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Insert: O(2) amortized. O(1) actual. |
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Union: O(1) amortized. O(1) actual. */ |
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|
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#ifndef _FIBHEAP_H_ |
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#define _FIBHEAP_H_ |
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|
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#include "ansidecl.h" |
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|
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#ifdef __cplusplus |
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extern "C" { |
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#endif |
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|
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typedef long fibheapkey_t; |
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|
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typedef struct fibheap |
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{ |
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size_t nodes; |
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struct fibnode *min; |
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struct fibnode *root; |
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} *fibheap_t; |
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|
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typedef struct fibnode |
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{ |
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struct fibnode *parent; |
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struct fibnode *child; |
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struct fibnode *left; |
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struct fibnode *right; |
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fibheapkey_t key; |
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void *data; |
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#if defined (__GNUC__) && (!defined (SIZEOF_INT) || SIZEOF_INT < 4) |
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__extension__ unsigned long int degree : 31; |
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__extension__ unsigned long int mark : 1; |
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#else |
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unsigned int degree : 31; |
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unsigned int mark : 1; |
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#endif |
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} *fibnode_t; |
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|
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extern fibheap_t fibheap_new (void); |
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extern fibnode_t fibheap_insert (fibheap_t, fibheapkey_t, void *); |
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extern int fibheap_empty (fibheap_t); |
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extern fibheapkey_t fibheap_min_key (fibheap_t); |
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extern fibheapkey_t fibheap_replace_key (fibheap_t, fibnode_t, |
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fibheapkey_t); |
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extern void *fibheap_replace_key_data (fibheap_t, fibnode_t, |
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fibheapkey_t, void *); |
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extern void *fibheap_extract_min (fibheap_t); |
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extern void *fibheap_min (fibheap_t); |
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extern void *fibheap_replace_data (fibheap_t, fibnode_t, void *); |
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extern void *fibheap_delete_node (fibheap_t, fibnode_t); |
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extern void fibheap_delete (fibheap_t); |
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extern fibheap_t fibheap_union (fibheap_t, fibheap_t); |
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|
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#ifdef __cplusplus |
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} |
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#endif |
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|
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#endif /* _FIBHEAP_H_ */ |
