diff --git a/include/ChangeLog b/include/ChangeLog index e76756bc6..b2b0f14e7 100644 --- a/include/ChangeLog +++ b/include/ChangeLog @@ -1,3 +1,7 @@ +2001-08-20 Daniel Berlin + + * fibheap.h: New file. Fibonacci heap. + 2001-08-20 Andrew Cagney * floatformat.h (floatformat_arm_ext): Document as deprecated. diff --git a/include/fibheap.h b/include/fibheap.h new file mode 100644 index 000000000..16db65e09 --- /dev/null +++ b/include/fibheap.h @@ -0,0 +1,80 @@ +/* A Fibonacci heap datatype. + Copyright 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + Contributed by Daniel Berlin (dan@cgsoftware.com). + +This file is part of GNU CC. + +GNU CC 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. + +GNU CC 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 GNU CC; see the file COPYING. If not, write to +the Free Software Foundation, 59 Temple Place - Suite 330, +Boston, MA 02111-1307, USA. */ + +/* Fibonacci heaps are somewhat complex, but, there's an + article in DDJ on them 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 + +typedef struct fibheap +{ + size_t nodes; + struct fibnode *min; + struct fibnode *root; +} *fibheap_t; +typedef long fibheapkey_t; +typedef struct fibnode +{ + struct fibnode *parent; + struct fibnode *child; + struct fibnode *left; + struct fibnode *right; + unsigned int degree : sizeof(size_t) * CHAR_BIT - 2; + unsigned int mark:1; + fibheapkey_t key; + void *data; +} *fibnode_t; + +extern fibheap_t fibheap_new PARAMS ((void)); +extern fibnode_t fibheap_insert PARAMS ((fibheap_t, fibheapkey_t, void *)); +extern int fibheap_empty PARAMS ((fibheap_t)); +extern fibheapkey_t fibheap_min_key PARAMS ((fibheap_t)); +extern fibheapkey_t fibheap_replace_key PARAMS ((fibheap_t, fibnode_t, fibheapkey_t)); +extern void *fibheap_replace_key_data PARAMS ((fibheap_t, fibnode_t, fibheapkey_t, void *)); +extern void *fibheap_extract_min PARAMS ((fibheap_t)); +extern void *fibheap_min PARAMS ((fibheap_t)); +extern void *fibheap_replace_data PARAMS ((fibheap_t, fibnode_t, void *)); +extern void *fibheap_delete_node PARAMS ((fibheap_t, fibnode_t)); +extern void fibheap_delete PARAMS ((fibheap_t)); +extern fibheap_t fibheap_union PARAMS ((fibheap_t, fibheap_t)); +#endif /* _FIBHEAP_H_ */