Warning: That file was not part of the compilation database. It may have many parsing errors.

1// Queue implementation -*- C++ -*-
2
3// Copyright (C) 2001-2017 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996,1997
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51/** @file bits/stl_queue.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{queue}
54 */
55
56#ifndef _STL_QUEUE_H
57#define _STL_QUEUE_H 1
58
59#include <bits/concept_check.h>
60#include <debug/debug.h>
61#if __cplusplus >= 201103L
62# include <bits/uses_allocator.h>
63#endif
64
65namespace std _GLIBCXX_VISIBILITY(default)
66{
67_GLIBCXX_BEGIN_NAMESPACE_VERSION
68
69 /**
70 * @brief A standard container giving FIFO behavior.
71 *
72 * @ingroup sequences
73 *
74 * @tparam _Tp Type of element.
75 * @tparam _Sequence Type of underlying sequence, defaults to deque<_Tp>.
76 *
77 * Meets many of the requirements of a
78 * <a href="tables.html#65">container</a>,
79 * but does not define anything to do with iterators. Very few of the
80 * other standard container interfaces are defined.
81 *
82 * This is not a true container, but an @e adaptor. It holds another
83 * container, and provides a wrapper interface to that container. The
84 * wrapper is what enforces strict first-in-first-out %queue behavior.
85 *
86 * The second template parameter defines the type of the underlying
87 * sequence/container. It defaults to std::deque, but it can be any type
88 * that supports @c front, @c back, @c push_back, and @c pop_front,
89 * such as std::list or an appropriate user-defined type.
90 *
91 * Members not found in @a normal containers are @c container_type,
92 * which is a typedef for the second Sequence parameter, and @c push and
93 * @c pop, which are standard %queue/FIFO operations.
94 */
95 template<typename _Tp, typename _Sequence = deque<_Tp> >
96 class queue
97 {
98#ifdef _GLIBCXX_CONCEPT_CHECKS
99 // concept requirements
100 typedef typename _Sequence::value_type _Sequence_value_type;
101# if __cplusplus < 201103L
102 __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
103# endif
104 __glibcxx_class_requires(_Sequence, _FrontInsertionSequenceConcept)
105 __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept)
106 __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
107#endif
108
109 template<typename _Tp1, typename _Seq1>
110 friend bool
111 operator==(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
112
113 template<typename _Tp1, typename _Seq1>
114 friend bool
115 operator<(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
116
117#if __cplusplus >= 201103L
118 template<typename _Alloc>
119 using _Uses = typename
120 enable_if<uses_allocator<_Sequence, _Alloc>::value>::type;
121#endif
122
123 public:
124 typedef typename _Sequence::value_type value_type;
125 typedef typename _Sequence::reference reference;
126 typedef typename _Sequence::const_reference const_reference;
127 typedef typename _Sequence::size_type size_type;
128 typedef _Sequence container_type;
129
130 protected:
131 /* Maintainers wondering why this isn't uglified as per style
132 * guidelines should note that this name is specified in the standard,
133 * C++98 [23.2.3.1].
134 * (Why? Presumably for the same reason that it's protected instead
135 * of private: to allow derivation. But none of the other
136 * containers allow for derivation. Odd.)
137 */
138 /// @c c is the underlying container.
139 _Sequence c;
140
141 public:
142 /**
143 * @brief Default constructor creates no elements.
144 */
145#if __cplusplus < 201103L
146 explicit
147 queue(const _Sequence& __c = _Sequence())
148 : c(__c) { }
149#else
150 template<typename _Seq = _Sequence, typename _Requires = typename
151 enable_if<is_default_constructible<_Seq>::value>::type>
152 queue()
153 : c() { }
154
155 explicit
156 queue(const _Sequence& __c)
157 : c(__c) { }
158
159 explicit
160 queue(_Sequence&& __c)
161 : c(std::move(__c)) { }
162
163 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
164 explicit
165 queue(const _Alloc& __a)
166 : c(__a) { }
167
168 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
169 queue(const _Sequence& __c, const _Alloc& __a)
170 : c(__c, __a) { }
171
172 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
173 queue(_Sequence&& __c, const _Alloc& __a)
174 : c(std::move(__c), __a) { }
175
176 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
177 queue(const queue& __q, const _Alloc& __a)
178 : c(__q.c, __a) { }
179
180 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
181 queue(queue&& __q, const _Alloc& __a)
182 : c(std::move(__q.c), __a) { }
183#endif
184
185 /**
186 * Returns true if the %queue is empty.
187 */
188 bool
189 empty() const
190 { return c.empty(); }
191
192 /** Returns the number of elements in the %queue. */
193 size_type
194 size() const
195 { return c.size(); }
196
197 /**
198 * Returns a read/write reference to the data at the first
199 * element of the %queue.
200 */
201 reference
202 front()
203 {
204 __glibcxx_requires_nonempty();
205 return c.front();
206 }
207
208 /**
209 * Returns a read-only (constant) reference to the data at the first
210 * element of the %queue.
211 */
212 const_reference
213 front() const
214 {
215 __glibcxx_requires_nonempty();
216 return c.front();
217 }
218
219 /**
220 * Returns a read/write reference to the data at the last
221 * element of the %queue.
222 */
223 reference
224 back()
225 {
226 __glibcxx_requires_nonempty();
227 return c.back();
228 }
229
230 /**
231 * Returns a read-only (constant) reference to the data at the last
232 * element of the %queue.
233 */
234 const_reference
235 back() const
236 {
237 __glibcxx_requires_nonempty();
238 return c.back();
239 }
240
241 /**
242 * @brief Add data to the end of the %queue.
243 * @param __x Data to be added.
244 *
245 * This is a typical %queue operation. The function creates an
246 * element at the end of the %queue and assigns the given data
247 * to it. The time complexity of the operation depends on the
248 * underlying sequence.
249 */
250 void
251 push(const value_type& __x)
252 { c.push_back(__x); }
253
254#if __cplusplus >= 201103L
255 void
256 push(value_type&& __x)
257 { c.push_back(std::move(__x)); }
258
259#if __cplusplus > 201402L
260 template<typename... _Args>
261 decltype(auto)
262 emplace(_Args&&... __args)
263 { return c.emplace_back(std::forward<_Args>(__args)...); }
264#else
265 template<typename... _Args>
266 void
267 emplace(_Args&&... __args)
268 { c.emplace_back(std::forward<_Args>(__args)...); }
269#endif
270#endif
271
272 /**
273 * @brief Removes first element.
274 *
275 * This is a typical %queue operation. It shrinks the %queue by one.
276 * The time complexity of the operation depends on the underlying
277 * sequence.
278 *
279 * Note that no data is returned, and if the first element's
280 * data is needed, it should be retrieved before pop() is
281 * called.
282 */
283 void
284 pop()
285 {
286 __glibcxx_requires_nonempty();
287 c.pop_front();
288 }
289
290#if __cplusplus >= 201103L
291 void
292 swap(queue& __q)
293#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
294 noexcept(__is_nothrow_swappable<_Sequence>::value)
295#else
296 noexcept(__is_nothrow_swappable<_Tp>::value)
297#endif
298 {
299 using std::swap;
300 swap(c, __q.c);
301 }
302#endif // __cplusplus >= 201103L
303 };
304
305 /**
306 * @brief Queue equality comparison.
307 * @param __x A %queue.
308 * @param __y A %queue of the same type as @a __x.
309 * @return True iff the size and elements of the queues are equal.
310 *
311 * This is an equivalence relation. Complexity and semantics depend on the
312 * underlying sequence type, but the expected rules are: this relation is
313 * linear in the size of the sequences, and queues are considered equivalent
314 * if their sequences compare equal.
315 */
316 template<typename _Tp, typename _Seq>
317 inline bool
318 operator==(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
319 { return __x.c == __y.c; }
320
321 /**
322 * @brief Queue ordering relation.
323 * @param __x A %queue.
324 * @param __y A %queue of the same type as @a x.
325 * @return True iff @a __x is lexicographically less than @a __y.
326 *
327 * This is an total ordering relation. Complexity and semantics
328 * depend on the underlying sequence type, but the expected rules
329 * are: this relation is linear in the size of the sequences, the
330 * elements must be comparable with @c <, and
331 * std::lexicographical_compare() is usually used to make the
332 * determination.
333 */
334 template<typename _Tp, typename _Seq>
335 inline bool
336 operator<(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
337 { return __x.c < __y.c; }
338
339 /// Based on operator==
340 template<typename _Tp, typename _Seq>
341 inline bool
342 operator!=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
343 { return !(__x == __y); }
344
345 /// Based on operator<
346 template<typename _Tp, typename _Seq>
347 inline bool
348 operator>(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
349 { return __y < __x; }
350
351 /// Based on operator<
352 template<typename _Tp, typename _Seq>
353 inline bool
354 operator<=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
355 { return !(__y < __x); }
356
357 /// Based on operator<
358 template<typename _Tp, typename _Seq>
359 inline bool
360 operator>=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
361 { return !(__x < __y); }
362
363#if __cplusplus >= 201103L
364 template<typename _Tp, typename _Seq>
365 inline
366#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
367 // Constrained free swap overload, see p0185r1
368 typename enable_if<__is_swappable<_Seq>::value>::type
369#else
370 void
371#endif
372 swap(queue<_Tp, _Seq>& __x, queue<_Tp, _Seq>& __y)
373 noexcept(noexcept(__x.swap(__y)))
374 { __x.swap(__y); }
375
376 template<typename _Tp, typename _Seq, typename _Alloc>
377 struct uses_allocator<queue<_Tp, _Seq>, _Alloc>
378 : public uses_allocator<_Seq, _Alloc>::type { };
379#endif // __cplusplus >= 201103L
380
381 /**
382 * @brief A standard container automatically sorting its contents.
383 *
384 * @ingroup sequences
385 *
386 * @tparam _Tp Type of element.
387 * @tparam _Sequence Type of underlying sequence, defaults to vector<_Tp>.
388 * @tparam _Compare Comparison function object type, defaults to
389 * less<_Sequence::value_type>.
390 *
391 * This is not a true container, but an @e adaptor. It holds
392 * another container, and provides a wrapper interface to that
393 * container. The wrapper is what enforces priority-based sorting
394 * and %queue behavior. Very few of the standard container/sequence
395 * interface requirements are met (e.g., iterators).
396 *
397 * The second template parameter defines the type of the underlying
398 * sequence/container. It defaults to std::vector, but it can be
399 * any type that supports @c front(), @c push_back, @c pop_back,
400 * and random-access iterators, such as std::deque or an
401 * appropriate user-defined type.
402 *
403 * The third template parameter supplies the means of making
404 * priority comparisons. It defaults to @c less<value_type> but
405 * can be anything defining a strict weak ordering.
406 *
407 * Members not found in @a normal containers are @c container_type,
408 * which is a typedef for the second Sequence parameter, and @c
409 * push, @c pop, and @c top, which are standard %queue operations.
410 *
411 * @note No equality/comparison operators are provided for
412 * %priority_queue.
413 *
414 * @note Sorting of the elements takes place as they are added to,
415 * and removed from, the %priority_queue using the
416 * %priority_queue's member functions. If you access the elements
417 * by other means, and change their data such that the sorting
418 * order would be different, the %priority_queue will not re-sort
419 * the elements for you. (How could it know to do so?)
420 */
421 template<typename _Tp, typename _Sequence = vector<_Tp>,
422 typename _Compare = less<typename _Sequence::value_type> >
423 class priority_queue
424 {
425#ifdef _GLIBCXX_CONCEPT_CHECKS
426 // concept requirements
427 typedef typename _Sequence::value_type _Sequence_value_type;
428# if __cplusplus < 201103L
429 __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
430# endif
431 __glibcxx_class_requires(_Sequence, _SequenceConcept)
432 __glibcxx_class_requires(_Sequence, _RandomAccessContainerConcept)
433 __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
434 __glibcxx_class_requires4(_Compare, bool, _Tp, _Tp,
435 _BinaryFunctionConcept)
436#endif
437
438#if __cplusplus >= 201103L
439 template<typename _Alloc>
440 using _Uses = typename
441 enable_if<uses_allocator<_Sequence, _Alloc>::value>::type;
442#endif
443
444 public:
445 typedef typename _Sequence::value_type value_type;
446 typedef typename _Sequence::reference reference;
447 typedef typename _Sequence::const_reference const_reference;
448 typedef typename _Sequence::size_type size_type;
449 typedef _Sequence container_type;
450 // _GLIBCXX_RESOLVE_LIB_DEFECTS
451 // DR 2684. priority_queue lacking comparator typedef
452 typedef _Compare value_compare;
453
454 protected:
455 // See queue::c for notes on these names.
456 _Sequence c;
457 _Compare comp;
458
459 public:
460 /**
461 * @brief Default constructor creates no elements.
462 */
463#if __cplusplus < 201103L
464 explicit
465 priority_queue(const _Compare& __x = _Compare(),
466 const _Sequence& __s = _Sequence())
467 : c(__s), comp(__x)
468 { std::make_heap(c.begin(), c.end(), comp); }
469#else
470 template<typename _Seq = _Sequence, typename _Requires = typename
471 enable_if<__and_<is_default_constructible<_Compare>,
472 is_default_constructible<_Seq>>::value>::type>
473 priority_queue()
474 : c(), comp() { }
475
476 explicit
477 priority_queue(const _Compare& __x, const _Sequence& __s)
478 : c(__s), comp(__x)
479 { std::make_heap(c.begin(), c.end(), comp); }
480
481 explicit
482 priority_queue(const _Compare& __x, _Sequence&& __s = _Sequence())
483 : c(std::move(__s)), comp(__x)
484 { std::make_heap(c.begin(), c.end(), comp); }
485
486 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
487 explicit
488 priority_queue(const _Alloc& __a)
489 : c(__a), comp() { }
490
491 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
492 priority_queue(const _Compare& __x, const _Alloc& __a)
493 : c(__a), comp(__x) { }
494
495 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
496 priority_queue(const _Compare& __x, const _Sequence& __c,
497 const _Alloc& __a)
498 : c(__c, __a), comp(__x) { }
499
500 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
501 priority_queue(const _Compare& __x, _Sequence&& __c, const _Alloc& __a)
502 : c(std::move(__c), __a), comp(__x) { }
503
504 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
505 priority_queue(const priority_queue& __q, const _Alloc& __a)
506 : c(__q.c, __a), comp(__q.comp) { }
507
508 template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
509 priority_queue(priority_queue&& __q, const _Alloc& __a)
510 : c(std::move(__q.c), __a), comp(std::move(__q.comp)) { }
511#endif
512
513 /**
514 * @brief Builds a %queue from a range.
515 * @param __first An input iterator.
516 * @param __last An input iterator.
517 * @param __x A comparison functor describing a strict weak ordering.
518 * @param __s An initial sequence with which to start.
519 *
520 * Begins by copying @a __s, inserting a copy of the elements
521 * from @a [first,last) into the copy of @a __s, then ordering
522 * the copy according to @a __x.
523 *
524 * For more information on function objects, see the
525 * documentation on @link functors functor base
526 * classes@endlink.
527 */
528#if __cplusplus < 201103L
529 template<typename _InputIterator>
530 priority_queue(_InputIterator __first, _InputIterator __last,
531 const _Compare& __x = _Compare(),
532 const _Sequence& __s = _Sequence())
533 : c(__s), comp(__x)
534 {
535 __glibcxx_requires_valid_range(__first, __last);
536 c.insert(c.end(), __first, __last);
537 std::make_heap(c.begin(), c.end(), comp);
538 }
539#else
540 template<typename _InputIterator>
541 priority_queue(_InputIterator __first, _InputIterator __last,
542 const _Compare& __x,
543 const _Sequence& __s)
544 : c(__s), comp(__x)
545 {
546 __glibcxx_requires_valid_range(__first, __last);
547 c.insert(c.end(), __first, __last);
548 std::make_heap(c.begin(), c.end(), comp);
549 }
550
551 template<typename _InputIterator>
552 priority_queue(_InputIterator __first, _InputIterator __last,
553 const _Compare& __x = _Compare(),
554 _Sequence&& __s = _Sequence())
555 : c(std::move(__s)), comp(__x)
556 {
557 __glibcxx_requires_valid_range(__first, __last);
558 c.insert(c.end(), __first, __last);
559 std::make_heap(c.begin(), c.end(), comp);
560 }
561#endif
562
563 /**
564 * Returns true if the %queue is empty.
565 */
566 bool
567 empty() const
568 { return c.empty(); }
569
570 /** Returns the number of elements in the %queue. */
571 size_type
572 size() const
573 { return c.size(); }
574
575 /**
576 * Returns a read-only (constant) reference to the data at the first
577 * element of the %queue.
578 */
579 const_reference
580 top() const
581 {
582 __glibcxx_requires_nonempty();
583 return c.front();
584 }
585
586 /**
587 * @brief Add data to the %queue.
588 * @param __x Data to be added.
589 *
590 * This is a typical %queue operation.
591 * The time complexity of the operation depends on the underlying
592 * sequence.
593 */
594 void
595 push(const value_type& __x)
596 {
597 c.push_back(__x);
598 std::push_heap(c.begin(), c.end(), comp);
599 }
600
601#if __cplusplus >= 201103L
602 void
603 push(value_type&& __x)
604 {
605 c.push_back(std::move(__x));
606 std::push_heap(c.begin(), c.end(), comp);
607 }
608
609 template<typename... _Args>
610 void
611 emplace(_Args&&... __args)
612 {
613 c.emplace_back(std::forward<_Args>(__args)...);
614 std::push_heap(c.begin(), c.end(), comp);
615 }
616#endif
617
618 /**
619 * @brief Removes first element.
620 *
621 * This is a typical %queue operation. It shrinks the %queue
622 * by one. The time complexity of the operation depends on the
623 * underlying sequence.
624 *
625 * Note that no data is returned, and if the first element's
626 * data is needed, it should be retrieved before pop() is
627 * called.
628 */
629 void
630 pop()
631 {
632 __glibcxx_requires_nonempty();
633 std::pop_heap(c.begin(), c.end(), comp);
634 c.pop_back();
635 }
636
637#if __cplusplus >= 201103L
638 void
639 swap(priority_queue& __pq)
640 noexcept(__and_<
641#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
642 __is_nothrow_swappable<_Sequence>,
643#else
644 __is_nothrow_swappable<_Tp>,
645#endif
646 __is_nothrow_swappable<_Compare>
647 >::value)
648 {
649 using std::swap;
650 swap(c, __pq.c);
651 swap(comp, __pq.comp);
652 }
653#endif // __cplusplus >= 201103L
654 };
655
656 // No equality/comparison operators are provided for priority_queue.
657
658#if __cplusplus >= 201103L
659 template<typename _Tp, typename _Sequence, typename _Compare>
660 inline
661#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
662 // Constrained free swap overload, see p0185r1
663 typename enable_if<__and_<__is_swappable<_Sequence>,
664 __is_swappable<_Compare>>::value>::type
665#else
666 void
667#endif
668 swap(priority_queue<_Tp, _Sequence, _Compare>& __x,
669 priority_queue<_Tp, _Sequence, _Compare>& __y)
670 noexcept(noexcept(__x.swap(__y)))
671 { __x.swap(__y); }
672
673 template<typename _Tp, typename _Sequence, typename _Compare,
674 typename _Alloc>
675 struct uses_allocator<priority_queue<_Tp, _Sequence, _Compare>, _Alloc>
676 : public uses_allocator<_Sequence, _Alloc>::type { };
677#endif // __cplusplus >= 201103L
678
679_GLIBCXX_END_NAMESPACE_VERSION
680} // namespace
681
682#endif /* _STL_QUEUE_H */
683

Warning: That file was not part of the compilation database. It may have many parsing errors.