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ba1a7a0f | 1 | /* Fibonacci heap for GNU compiler. |
a5544970 | 2 | Copyright (C) 1998-2019 Free Software Foundation, Inc. |
4a910049 ML |
3 | Contributed by Daniel Berlin (dan@cgsoftware.com). |
4 | Re-implemented in C++ by Martin Liska <mliska@suse.cz> | |
5 | ||
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify it under | |
9 | the terms of the GNU General Public License as published by the Free | |
10 | Software Foundation; either version 3, or (at your option) any later | |
11 | version. | |
12 | ||
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with GCC; see the file COPYING3. If not see | |
20 | <http://www.gnu.org/licenses/>. */ | |
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(1) amortized. | |
38 | Union: O(1) amortized. */ | |
39 | ||
40 | #ifndef GCC_FIBONACCI_HEAP_H | |
41 | #define GCC_FIBONACCI_HEAP_H | |
42 | ||
43 | /* Forward definition. */ | |
44 | ||
45 | template<class K, class V> | |
46 | class fibonacci_heap; | |
47 | ||
48 | /* Fibonacci heap node class. */ | |
49 | ||
50 | template<class K, class V> | |
51 | class fibonacci_node | |
52 | { | |
53 | typedef fibonacci_node<K,V> fibonacci_node_t; | |
54 | friend class fibonacci_heap<K,V>; | |
55 | ||
56 | public: | |
57 | /* Default constructor. */ | |
58 | fibonacci_node (): m_parent (NULL), m_child (NULL), m_left (this), | |
59 | m_right (this), m_degree (0), m_mark (0) | |
60 | { | |
61 | } | |
62 | ||
63 | /* Constructor for a node with given KEY. */ | |
ba1a7a0f ML |
64 | fibonacci_node (K key, V *data = NULL): m_parent (NULL), m_child (NULL), |
65 | m_left (this), m_right (this), m_key (key), m_data (data), | |
4a910049 ML |
66 | m_degree (0), m_mark (0) |
67 | { | |
68 | } | |
69 | ||
70 | /* Compare fibonacci node with OTHER node. */ | |
71 | int compare (fibonacci_node_t *other) | |
72 | { | |
73 | if (m_key < other->m_key) | |
74 | return -1; | |
75 | if (m_key > other->m_key) | |
76 | return 1; | |
77 | return 0; | |
78 | } | |
79 | ||
80 | /* Compare the node with a given KEY. */ | |
81 | int compare_data (K key) | |
82 | { | |
83 | return fibonacci_node_t (key).compare (this); | |
84 | } | |
85 | ||
86 | /* Remove fibonacci heap node. */ | |
87 | fibonacci_node_t *remove (); | |
88 | ||
89 | /* Link the node with PARENT. */ | |
90 | void link (fibonacci_node_t *parent); | |
91 | ||
92 | /* Return key associated with the node. */ | |
93 | K get_key () | |
94 | { | |
95 | return m_key; | |
96 | } | |
97 | ||
98 | /* Return data associated with the node. */ | |
99 | V *get_data () | |
100 | { | |
101 | return m_data; | |
102 | } | |
103 | ||
104 | private: | |
105 | /* Put node B after this node. */ | |
106 | void insert_after (fibonacci_node_t *b); | |
107 | ||
108 | /* Insert fibonacci node B after this node. */ | |
109 | void insert_before (fibonacci_node_t *b) | |
110 | { | |
111 | m_left->insert_after (b); | |
112 | } | |
113 | ||
114 | /* Parent node. */ | |
115 | fibonacci_node *m_parent; | |
116 | /* Child node. */ | |
117 | fibonacci_node *m_child; | |
118 | /* Left sibling. */ | |
119 | fibonacci_node *m_left; | |
120 | /* Right node. */ | |
121 | fibonacci_node *m_right; | |
122 | /* Key associated with node. */ | |
123 | K m_key; | |
124 | /* Data associated with node. */ | |
125 | V *m_data; | |
126 | ||
127 | #if defined (__GNUC__) && (!defined (SIZEOF_INT) || SIZEOF_INT < 4) | |
128 | /* Degree of the node. */ | |
129 | __extension__ unsigned long int m_degree : 31; | |
130 | /* Mark of the node. */ | |
131 | __extension__ unsigned long int m_mark : 1; | |
132 | #else | |
133 | /* Degree of the node. */ | |
134 | unsigned int m_degree : 31; | |
135 | /* Mark of the node. */ | |
136 | unsigned int m_mark : 1; | |
137 | #endif | |
138 | }; | |
139 | ||
140 | /* Fibonacci heap class. */ | |
141 | template<class K, class V> | |
142 | class fibonacci_heap | |
143 | { | |
144 | typedef fibonacci_node<K,V> fibonacci_node_t; | |
145 | friend class fibonacci_node<K,V>; | |
146 | ||
147 | public: | |
148 | /* Default constructor. */ | |
149 | fibonacci_heap (K global_min_key): m_nodes (0), m_min (NULL), m_root (NULL), | |
150 | m_global_min_key (global_min_key) | |
151 | { | |
152 | } | |
153 | ||
154 | /* Destructor. */ | |
155 | ~fibonacci_heap () | |
156 | { | |
157 | while (m_min != NULL) | |
158 | delete (extract_minimum_node ()); | |
159 | } | |
160 | ||
161 | /* Insert new node given by KEY and DATA associated with the key. */ | |
162 | fibonacci_node_t *insert (K key, V *data); | |
163 | ||
164 | /* Return true if no entry is present. */ | |
26a23d11 | 165 | bool empty () const |
4a910049 ML |
166 | { |
167 | return m_nodes == 0; | |
168 | } | |
169 | ||
170 | /* Return the number of nodes. */ | |
26a23d11 | 171 | size_t nodes () const |
4a910049 ML |
172 | { |
173 | return m_nodes; | |
174 | } | |
175 | ||
176 | /* Return minimal key presented in the heap. */ | |
26a23d11 | 177 | K min_key () const |
4a910049 ML |
178 | { |
179 | if (m_min == NULL) | |
180 | gcc_unreachable (); | |
181 | ||
182 | return m_min->m_key; | |
183 | } | |
184 | ||
185 | /* For given NODE, set new KEY value. */ | |
a3dc1a45 | 186 | K replace_key (fibonacci_node_t *node, K key) |
4a910049 ML |
187 | { |
188 | K okey = node->m_key; | |
4a910049 ML |
189 | |
190 | replace_key_data (node, key, node->m_data); | |
191 | return okey; | |
192 | } | |
193 | ||
a3dc1a45 ML |
194 | /* For given NODE, decrease value to new KEY. */ |
195 | K decrease_key (fibonacci_node_t *node, K key) | |
196 | { | |
197 | gcc_assert (key <= node->m_key); | |
198 | return replace_key (node, key); | |
199 | } | |
200 | ||
4a910049 ML |
201 | /* For given NODE, set new KEY and DATA value. */ |
202 | V *replace_key_data (fibonacci_node_t *node, K key, V *data); | |
203 | ||
a3dc1a45 ML |
204 | /* Extract minimum node in the heap. If RELEASE is specified, |
205 | memory is released. */ | |
206 | V *extract_min (bool release = true); | |
4a910049 ML |
207 | |
208 | /* Return value associated with minimum node in the heap. */ | |
26a23d11 | 209 | V *min () const |
4a910049 ML |
210 | { |
211 | if (m_min == NULL) | |
212 | return NULL; | |
213 | ||
c0f15a3f | 214 | return m_min->m_data; |
4a910049 ML |
215 | } |
216 | ||
217 | /* Replace data associated with NODE and replace it with DATA. */ | |
218 | V *replace_data (fibonacci_node_t *node, V *data) | |
219 | { | |
220 | return replace_key_data (node, node->m_key, data); | |
221 | } | |
222 | ||
223 | /* Delete NODE in the heap. */ | |
a3dc1a45 | 224 | V *delete_node (fibonacci_node_t *node, bool release = true); |
4a910049 ML |
225 | |
226 | /* Union the heap with HEAPB. */ | |
227 | fibonacci_heap *union_with (fibonacci_heap *heapb); | |
228 | ||
229 | private: | |
a3dc1a45 ML |
230 | /* Insert new NODE given by KEY and DATA associated with the key. */ |
231 | fibonacci_node_t *insert (fibonacci_node_t *node, K key, V *data); | |
232 | ||
ba1a7a0f ML |
233 | /* Insert new NODE that has already filled key and value. */ |
234 | fibonacci_node_t *insert_node (fibonacci_node_t *node); | |
235 | ||
4a910049 ML |
236 | /* Insert it into the root list. */ |
237 | void insert_root (fibonacci_node_t *node); | |
238 | ||
239 | /* Remove NODE from PARENT's child list. */ | |
240 | void cut (fibonacci_node_t *node, fibonacci_node_t *parent); | |
241 | ||
242 | /* Process cut of node Y and do it recursivelly. */ | |
243 | void cascading_cut (fibonacci_node_t *y); | |
244 | ||
245 | /* Extract minimum node from the heap. */ | |
246 | fibonacci_node_t * extract_minimum_node (); | |
247 | ||
248 | /* Remove root NODE from the heap. */ | |
249 | void remove_root (fibonacci_node_t *node); | |
250 | ||
251 | /* Consolidate heap. */ | |
252 | void consolidate (); | |
253 | ||
254 | /* Number of nodes. */ | |
255 | size_t m_nodes; | |
256 | /* Minimum node of the heap. */ | |
257 | fibonacci_node_t *m_min; | |
258 | /* Root node of the heap. */ | |
259 | fibonacci_node_t *m_root; | |
260 | /* Global minimum given in the heap construction. */ | |
261 | K m_global_min_key; | |
262 | }; | |
263 | ||
264 | /* Remove fibonacci heap node. */ | |
265 | ||
266 | template<class K, class V> | |
267 | fibonacci_node<K,V> * | |
268 | fibonacci_node<K,V>::remove () | |
269 | { | |
270 | fibonacci_node<K,V> *ret; | |
271 | ||
272 | if (this == m_left) | |
273 | ret = NULL; | |
274 | else | |
275 | ret = m_left; | |
276 | ||
277 | if (m_parent != NULL && m_parent->m_child == this) | |
278 | m_parent->m_child = ret; | |
279 | ||
280 | m_right->m_left = m_left; | |
281 | m_left->m_right = m_right; | |
282 | ||
283 | m_parent = NULL; | |
284 | m_left = this; | |
285 | m_right = this; | |
286 | ||
287 | return ret; | |
288 | } | |
289 | ||
290 | /* Link the node with PARENT. */ | |
291 | ||
292 | template<class K, class V> | |
293 | void | |
294 | fibonacci_node<K,V>::link (fibonacci_node<K,V> *parent) | |
295 | { | |
296 | if (parent->m_child == NULL) | |
297 | parent->m_child = this; | |
298 | else | |
299 | parent->m_child->insert_before (this); | |
300 | m_parent = parent; | |
301 | parent->m_degree++; | |
302 | m_mark = 0; | |
303 | } | |
304 | ||
305 | /* Put node B after this node. */ | |
306 | ||
307 | template<class K, class V> | |
308 | void | |
309 | fibonacci_node<K,V>::insert_after (fibonacci_node<K,V> *b) | |
310 | { | |
311 | fibonacci_node<K,V> *a = this; | |
312 | ||
313 | if (a == a->m_right) | |
314 | { | |
315 | a->m_right = b; | |
316 | a->m_left = b; | |
317 | b->m_right = a; | |
318 | b->m_left = a; | |
319 | } | |
320 | else | |
321 | { | |
322 | b->m_right = a->m_right; | |
323 | a->m_right->m_left = b; | |
324 | a->m_right = b; | |
325 | b->m_left = a; | |
326 | } | |
327 | } | |
328 | ||
329 | /* Insert new node given by KEY and DATA associated with the key. */ | |
330 | ||
331 | template<class K, class V> | |
332 | fibonacci_node<K,V>* | |
333 | fibonacci_heap<K,V>::insert (K key, V *data) | |
334 | { | |
335 | /* Create the new node. */ | |
ba1a7a0f | 336 | fibonacci_node<K,V> *node = new fibonacci_node_t (key, data); |
4a910049 | 337 | |
ba1a7a0f | 338 | return insert_node (node); |
a3dc1a45 ML |
339 | } |
340 | ||
ba1a7a0f | 341 | /* Insert new NODE given by DATA associated with the key. */ |
a3dc1a45 ML |
342 | |
343 | template<class K, class V> | |
344 | fibonacci_node<K,V>* | |
345 | fibonacci_heap<K,V>::insert (fibonacci_node_t *node, K key, V *data) | |
346 | { | |
4a910049 ML |
347 | /* Set the node's data. */ |
348 | node->m_data = data; | |
349 | node->m_key = key; | |
350 | ||
ba1a7a0f ML |
351 | return insert_node (node); |
352 | } | |
353 | ||
354 | /* Insert new NODE that has already filled key and value. */ | |
355 | ||
356 | template<class K, class V> | |
357 | fibonacci_node<K,V>* | |
358 | fibonacci_heap<K,V>::insert_node (fibonacci_node_t *node) | |
359 | { | |
4a910049 ML |
360 | /* Insert it into the root list. */ |
361 | insert_root (node); | |
362 | ||
363 | /* If their was no minimum, or this key is less than the min, | |
364 | it's the new min. */ | |
365 | if (m_min == NULL || node->m_key < m_min->m_key) | |
366 | m_min = node; | |
367 | ||
368 | m_nodes++; | |
369 | ||
370 | return node; | |
371 | } | |
372 | ||
373 | /* For given NODE, set new KEY and DATA value. */ | |
ba1a7a0f | 374 | |
4a910049 ML |
375 | template<class K, class V> |
376 | V* | |
377 | fibonacci_heap<K,V>::replace_key_data (fibonacci_node<K,V> *node, K key, | |
378 | V *data) | |
379 | { | |
4a910049 ML |
380 | K okey; |
381 | fibonacci_node<K,V> *y; | |
a3dc1a45 | 382 | V *odata = node->m_data; |
4a910049 | 383 | |
a3dc1a45 ML |
384 | /* If we wanted to, we do a real increase by redeleting and |
385 | inserting. */ | |
4a910049 | 386 | if (node->compare_data (key) > 0) |
a3dc1a45 ML |
387 | { |
388 | delete_node (node, false); | |
389 | ||
390 | node = new (node) fibonacci_node_t (); | |
391 | insert (node, key, data); | |
392 | ||
393 | return odata; | |
394 | } | |
4a910049 | 395 | |
4a910049 ML |
396 | okey = node->m_key; |
397 | node->m_data = data; | |
398 | node->m_key = key; | |
399 | y = node->m_parent; | |
400 | ||
401 | /* Short-circuit if the key is the same, as we then don't have to | |
402 | do anything. Except if we're trying to force the new node to | |
403 | be the new minimum for delete. */ | |
404 | if (okey == key && okey != m_global_min_key) | |
405 | return odata; | |
406 | ||
407 | /* These two compares are specifically <= 0 to make sure that in the case | |
408 | of equality, a node we replaced the data on, becomes the new min. This | |
409 | is needed so that delete's call to extractmin gets the right node. */ | |
410 | if (y != NULL && node->compare (y) <= 0) | |
411 | { | |
412 | cut (node, y); | |
413 | cascading_cut (y); | |
414 | } | |
415 | ||
416 | if (node->compare (m_min) <= 0) | |
417 | m_min = node; | |
418 | ||
419 | return odata; | |
420 | } | |
421 | ||
ba1a7a0f ML |
422 | /* Extract minimum node in the heap. Delete fibonacci node if RELEASE |
423 | is true. */ | |
424 | ||
4a910049 ML |
425 | template<class K, class V> |
426 | V* | |
a3dc1a45 | 427 | fibonacci_heap<K,V>::extract_min (bool release) |
4a910049 ML |
428 | { |
429 | fibonacci_node<K,V> *z; | |
430 | V *ret = NULL; | |
431 | ||
432 | /* If we don't have a min set, it means we have no nodes. */ | |
433 | if (m_min != NULL) | |
434 | { | |
435 | /* Otherwise, extract the min node, free the node, and return the | |
436 | node's data. */ | |
437 | z = extract_minimum_node (); | |
438 | ret = z->m_data; | |
a3dc1a45 ML |
439 | |
440 | if (release) | |
441 | delete (z); | |
4a910049 ML |
442 | } |
443 | ||
444 | return ret; | |
445 | } | |
446 | ||
a3dc1a45 | 447 | /* Delete NODE in the heap, if RELEASE is specified memory is released. */ |
4a910049 ML |
448 | |
449 | template<class K, class V> | |
450 | V* | |
a3dc1a45 | 451 | fibonacci_heap<K,V>::delete_node (fibonacci_node<K,V> *node, bool release) |
4a910049 ML |
452 | { |
453 | V *ret = node->m_data; | |
454 | ||
455 | /* To perform delete, we just make it the min key, and extract. */ | |
a3dc1a45 | 456 | replace_key (node, m_global_min_key); |
4a910049 ML |
457 | if (node != m_min) |
458 | { | |
459 | fprintf (stderr, "Can't force minimum on fibheap.\n"); | |
460 | abort (); | |
461 | } | |
a3dc1a45 | 462 | extract_min (release); |
4a910049 ML |
463 | |
464 | return ret; | |
465 | } | |
466 | ||
ba1a7a0f | 467 | /* Union the heap with HEAPB. One of the heaps is going to be deleted. */ |
4a910049 ML |
468 | |
469 | template<class K, class V> | |
470 | fibonacci_heap<K,V>* | |
471 | fibonacci_heap<K,V>::union_with (fibonacci_heap<K,V> *heapb) | |
472 | { | |
473 | fibonacci_heap<K,V> *heapa = this; | |
474 | ||
fab27f52 | 475 | fibonacci_node<K,V> *a_root, *b_root; |
4a910049 ML |
476 | |
477 | /* If one of the heaps is empty, the union is just the other heap. */ | |
478 | if ((a_root = heapa->m_root) == NULL) | |
479 | { | |
480 | delete (heapa); | |
481 | return heapb; | |
482 | } | |
483 | if ((b_root = heapb->m_root) == NULL) | |
484 | { | |
485 | delete (heapb); | |
486 | return heapa; | |
487 | } | |
488 | ||
489 | /* Merge them to the next nodes on the opposite chain. */ | |
490 | a_root->m_left->m_right = b_root; | |
491 | b_root->m_left->m_right = a_root; | |
fab27f52 | 492 | std::swap (a_root->m_left, b_root->m_left); |
4a910049 ML |
493 | heapa->m_nodes += heapb->m_nodes; |
494 | ||
495 | /* And set the new minimum, if it's changed. */ | |
ba1a7a0f | 496 | if (heapb->m_min->compare (heapa->m_min) < 0) |
4a910049 ML |
497 | heapa->m_min = heapb->m_min; |
498 | ||
ba1a7a0f ML |
499 | /* Set m_min to NULL to not to delete live fibonacci nodes. */ |
500 | heapb->m_min = NULL; | |
4a910049 | 501 | delete (heapb); |
ba1a7a0f | 502 | |
4a910049 ML |
503 | return heapa; |
504 | } | |
505 | ||
506 | /* Insert it into the root list. */ | |
507 | ||
508 | template<class K, class V> | |
509 | void | |
510 | fibonacci_heap<K,V>::insert_root (fibonacci_node_t *node) | |
511 | { | |
512 | /* If the heap is currently empty, the new node becomes the singleton | |
513 | circular root list. */ | |
514 | if (m_root == NULL) | |
515 | { | |
516 | m_root = node; | |
517 | node->m_left = node; | |
518 | node->m_right = node; | |
519 | return; | |
520 | } | |
521 | ||
522 | /* Otherwise, insert it in the circular root list between the root | |
523 | and it's right node. */ | |
524 | m_root->insert_after (node); | |
525 | } | |
526 | ||
527 | /* Remove NODE from PARENT's child list. */ | |
528 | ||
529 | template<class K, class V> | |
530 | void | |
531 | fibonacci_heap<K,V>::cut (fibonacci_node<K,V> *node, | |
532 | fibonacci_node<K,V> *parent) | |
533 | { | |
534 | node->remove (); | |
535 | parent->m_degree--; | |
536 | insert_root (node); | |
537 | node->m_parent = NULL; | |
538 | node->m_mark = 0; | |
539 | } | |
540 | ||
541 | /* Process cut of node Y and do it recursivelly. */ | |
542 | ||
543 | template<class K, class V> | |
544 | void | |
545 | fibonacci_heap<K,V>::cascading_cut (fibonacci_node<K,V> *y) | |
546 | { | |
547 | fibonacci_node<K,V> *z; | |
548 | ||
549 | while ((z = y->m_parent) != NULL) | |
550 | { | |
551 | if (y->m_mark == 0) | |
552 | { | |
553 | y->m_mark = 1; | |
554 | return; | |
555 | } | |
556 | else | |
557 | { | |
558 | cut (y, z); | |
559 | y = z; | |
560 | } | |
561 | } | |
562 | } | |
563 | ||
564 | /* Extract minimum node from the heap. */ | |
ba1a7a0f | 565 | |
4a910049 ML |
566 | template<class K, class V> |
567 | fibonacci_node<K,V>* | |
568 | fibonacci_heap<K,V>::extract_minimum_node () | |
569 | { | |
570 | fibonacci_node<K,V> *ret = m_min; | |
571 | fibonacci_node<K,V> *x, *y, *orig; | |
572 | ||
573 | /* Attach the child list of the minimum node to the root list of the heap. | |
574 | If there is no child list, we don't do squat. */ | |
575 | for (x = ret->m_child, orig = NULL; x != orig && x != NULL; x = y) | |
576 | { | |
577 | if (orig == NULL) | |
578 | orig = x; | |
579 | y = x->m_right; | |
580 | x->m_parent = NULL; | |
581 | insert_root (x); | |
582 | } | |
583 | ||
584 | /* Remove the old root. */ | |
585 | remove_root (ret); | |
586 | m_nodes--; | |
587 | ||
588 | /* If we are left with no nodes, then the min is NULL. */ | |
589 | if (m_nodes == 0) | |
590 | m_min = NULL; | |
591 | else | |
592 | { | |
593 | /* Otherwise, consolidate to find new minimum, as well as do the reorg | |
594 | work that needs to be done. */ | |
595 | m_min = ret->m_right; | |
596 | consolidate (); | |
597 | } | |
598 | ||
599 | return ret; | |
600 | } | |
601 | ||
602 | /* Remove root NODE from the heap. */ | |
603 | ||
604 | template<class K, class V> | |
605 | void | |
606 | fibonacci_heap<K,V>::remove_root (fibonacci_node<K,V> *node) | |
607 | { | |
608 | if (node->m_left == node) | |
609 | m_root = NULL; | |
610 | else | |
611 | m_root = node->remove (); | |
612 | } | |
613 | ||
614 | /* Consolidate heap. */ | |
615 | ||
616 | template<class K, class V> | |
617 | void fibonacci_heap<K,V>::consolidate () | |
618 | { | |
619 | int D = 1 + 8 * sizeof (long); | |
620 | auto_vec<fibonacci_node<K,V> *> a (D); | |
621 | a.safe_grow_cleared (D); | |
622 | fibonacci_node<K,V> *w, *x, *y; | |
623 | int i, d; | |
624 | ||
625 | while ((w = m_root) != NULL) | |
626 | { | |
627 | x = w; | |
628 | remove_root (w); | |
629 | d = x->m_degree; | |
630 | while (a[d] != NULL) | |
631 | { | |
632 | y = a[d]; | |
633 | if (x->compare (y) > 0) | |
634 | std::swap (x, y); | |
635 | y->link (x); | |
636 | a[d] = NULL; | |
637 | d++; | |
638 | } | |
639 | a[d] = x; | |
640 | } | |
641 | m_min = NULL; | |
642 | for (i = 0; i < D; i++) | |
643 | if (a[i] != NULL) | |
644 | { | |
645 | insert_root (a[i]); | |
646 | if (m_min == NULL || a[i]->compare (m_min) < 0) | |
647 | m_min = a[i]; | |
648 | } | |
649 | } | |
650 | ||
651 | #endif // GCC_FIBONACCI_HEAP_H |