1 // Multiset 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
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_multiset.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{set}
54 */
55
56 #ifndef _STL_MULTISET_H
57 #define _STL_MULTISET_H 1
58
59 #include <bits/concept_check.h>
60 #if __cplusplus >= 201103L
61 #include <initializer_list>
62 #endif
63
_GLIBCXX_VISIBILITY(default)64 namespace std _GLIBCXX_VISIBILITY(default)
65 {
66 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
67
68 template<typename _Key, typename _Compare, typename _Alloc>
69 class set;
70
71 /**
72 * @brief A standard container made up of elements, which can be retrieved
73 * in logarithmic time.
74 *
75 * @ingroup associative_containers
76 *
77 *
78 * @tparam _Key Type of key objects.
79 * @tparam _Compare Comparison function object type, defaults to less<_Key>.
80 * @tparam _Alloc Allocator type, defaults to allocator<_Key>.
81 *
82 * Meets the requirements of a <a href="tables.html#65">container</a>, a
83 * <a href="tables.html#66">reversible container</a>, and an
84 * <a href="tables.html#69">associative container</a> (using equivalent
85 * keys). For a @c multiset<Key> the key_type and value_type are Key.
86 *
87 * Multisets support bidirectional iterators.
88 *
89 * The private tree data is declared exactly the same way for set and
90 * multiset; the distinction is made entirely in how the tree functions are
91 * called (*_unique versus *_equal, same as the standard).
92 */
93 template <typename _Key, typename _Compare = std::less<_Key>,
94 typename _Alloc = std::allocator<_Key> >
95 class multiset
96 {
97 #ifdef _GLIBCXX_CONCEPT_CHECKS
98 // concept requirements
99 typedef typename _Alloc::value_type _Alloc_value_type;
100 # if __cplusplus < 201103L
101 __glibcxx_class_requires(_Key, _SGIAssignableConcept)
102 # endif
103 __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
104 _BinaryFunctionConcept)
105 __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept)
106 #endif
107
108 public:
109 // typedefs:
110 typedef _Key key_type;
111 typedef _Key value_type;
112 typedef _Compare key_compare;
113 typedef _Compare value_compare;
114 typedef _Alloc allocator_type;
115
116 private:
117 /// This turns a red-black tree into a [multi]set.
118 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
119 rebind<_Key>::other _Key_alloc_type;
120
121 typedef _Rb_tree<key_type, value_type, _Identity<value_type>,
122 key_compare, _Key_alloc_type> _Rep_type;
123 /// The actual tree structure.
124 _Rep_type _M_t;
125
126 typedef __gnu_cxx::__alloc_traits<_Key_alloc_type> _Alloc_traits;
127
128 public:
129 typedef typename _Alloc_traits::pointer pointer;
130 typedef typename _Alloc_traits::const_pointer const_pointer;
131 typedef typename _Alloc_traits::reference reference;
132 typedef typename _Alloc_traits::const_reference const_reference;
133 // _GLIBCXX_RESOLVE_LIB_DEFECTS
134 // DR 103. set::iterator is required to be modifiable,
135 // but this allows modification of keys.
136 typedef typename _Rep_type::const_iterator iterator;
137 typedef typename _Rep_type::const_iterator const_iterator;
138 typedef typename _Rep_type::const_reverse_iterator reverse_iterator;
139 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
140 typedef typename _Rep_type::size_type size_type;
141 typedef typename _Rep_type::difference_type difference_type;
142
143 #if __cplusplus > 201402L
144 using node_type = typename _Rep_type::node_type;
145 #endif
146
147 // allocation/deallocation
148 /**
149 * @brief Default constructor creates no elements.
150 */
151 #if __cplusplus < 201103L
152 multiset() : _M_t() { }
153 #else
154 multiset() = default;
155 #endif
156
157 /**
158 * @brief Creates a %multiset with no elements.
159 * @param __comp Comparator to use.
160 * @param __a An allocator object.
161 */
162 explicit
163 multiset(const _Compare& __comp,
164 const allocator_type& __a = allocator_type())
165 : _M_t(__comp, _Key_alloc_type(__a)) { }
166
167 /**
168 * @brief Builds a %multiset from a range.
169 * @param __first An input iterator.
170 * @param __last An input iterator.
171 *
172 * Create a %multiset consisting of copies of the elements from
173 * [first,last). This is linear in N if the range is already sorted,
174 * and NlogN otherwise (where N is distance(__first,__last)).
175 */
176 template<typename _InputIterator>
177 multiset(_InputIterator __first, _InputIterator __last)
178 : _M_t()
179 { _M_t._M_insert_equal(__first, __last); }
180
181 /**
182 * @brief Builds a %multiset from a range.
183 * @param __first An input iterator.
184 * @param __last An input iterator.
185 * @param __comp A comparison functor.
186 * @param __a An allocator object.
187 *
188 * Create a %multiset consisting of copies of the elements from
189 * [__first,__last). This is linear in N if the range is already sorted,
190 * and NlogN otherwise (where N is distance(__first,__last)).
191 */
192 template<typename _InputIterator>
193 multiset(_InputIterator __first, _InputIterator __last,
194 const _Compare& __comp,
195 const allocator_type& __a = allocator_type())
196 : _M_t(__comp, _Key_alloc_type(__a))
197 { _M_t._M_insert_equal(__first, __last); }
198
199 /**
200 * @brief %Multiset copy constructor.
201 *
202 * Whether the allocator is copied depends on the allocator traits.
203 */
204 #if __cplusplus < 201103L
205 multiset(const multiset& __x)
206 : _M_t(__x._M_t) { }
207 #else
208 multiset(const multiset&) = default;
209
210 /**
211 * @brief %Multiset move constructor.
212 *
213 * The newly-created %multiset contains the exact contents of the
214 * moved instance. The moved instance is a valid, but unspecified
215 * %multiset.
216 */
217 multiset(multiset&&) = default;
218
219 /**
220 * @brief Builds a %multiset from an initializer_list.
221 * @param __l An initializer_list.
222 * @param __comp A comparison functor.
223 * @param __a An allocator object.
224 *
225 * Create a %multiset consisting of copies of the elements from
226 * the list. This is linear in N if the list is already sorted,
227 * and NlogN otherwise (where N is @a __l.size()).
228 */
229 multiset(initializer_list<value_type> __l,
230 const _Compare& __comp = _Compare(),
231 const allocator_type& __a = allocator_type())
232 : _M_t(__comp, _Key_alloc_type(__a))
233 { _M_t._M_insert_equal(__l.begin(), __l.end()); }
234
235 /// Allocator-extended default constructor.
236 explicit
237 multiset(const allocator_type& __a)
238 : _M_t(_Compare(), _Key_alloc_type(__a)) { }
239
240 /// Allocator-extended copy constructor.
241 multiset(const multiset& __m, const allocator_type& __a)
242 : _M_t(__m._M_t, _Key_alloc_type(__a)) { }
243
244 /// Allocator-extended move constructor.
245 multiset(multiset&& __m, const allocator_type& __a)
246 noexcept(is_nothrow_copy_constructible<_Compare>::value
247 && _Alloc_traits::_S_always_equal())
248 : _M_t(std::move(__m._M_t), _Key_alloc_type(__a)) { }
249
250 /// Allocator-extended initialier-list constructor.
251 multiset(initializer_list<value_type> __l, const allocator_type& __a)
252 : _M_t(_Compare(), _Key_alloc_type(__a))
253 { _M_t._M_insert_equal(__l.begin(), __l.end()); }
254
255 /// Allocator-extended range constructor.
256 template<typename _InputIterator>
257 multiset(_InputIterator __first, _InputIterator __last,
258 const allocator_type& __a)
259 : _M_t(_Compare(), _Key_alloc_type(__a))
260 { _M_t._M_insert_equal(__first, __last); }
261
262 /**
263 * The dtor only erases the elements, and note that if the elements
264 * themselves are pointers, the pointed-to memory is not touched in any
265 * way. Managing the pointer is the user's responsibility.
266 */
267 ~multiset() = default;
268 #endif
269
270 /**
271 * @brief %Multiset assignment operator.
272 *
273 * Whether the allocator is copied depends on the allocator traits.
274 */
275 #if __cplusplus < 201103L
276 multiset&
277 operator=(const multiset& __x)
278 {
279 _M_t = __x._M_t;
280 return *this;
281 }
282 #else
283 multiset&
284 operator=(const multiset&) = default;
285
286 /// Move assignment operator.
287 multiset&
288 operator=(multiset&&) = default;
289
290 /**
291 * @brief %Multiset list assignment operator.
292 * @param __l An initializer_list.
293 *
294 * This function fills a %multiset with copies of the elements in the
295 * initializer list @a __l.
296 *
297 * Note that the assignment completely changes the %multiset and
298 * that the resulting %multiset's size is the same as the number
299 * of elements assigned.
300 */
301 multiset&
302 operator=(initializer_list<value_type> __l)
303 {
304 _M_t._M_assign_equal(__l.begin(), __l.end());
305 return *this;
306 }
307 #endif
308
309 // accessors:
310
311 /// Returns the comparison object.
312 key_compare
313 key_comp() const
314 { return _M_t.key_comp(); }
315 /// Returns the comparison object.
316 value_compare
317 value_comp() const
318 { return _M_t.key_comp(); }
319 /// Returns the memory allocation object.
320 allocator_type
321 get_allocator() const _GLIBCXX_NOEXCEPT
322 { return allocator_type(_M_t.get_allocator()); }
323
324 /**
325 * Returns a read-only (constant) iterator that points to the first
326 * element in the %multiset. Iteration is done in ascending order
327 * according to the keys.
328 */
329 iterator
330 begin() const _GLIBCXX_NOEXCEPT
331 { return _M_t.begin(); }
332
333 /**
334 * Returns a read-only (constant) iterator that points one past the last
335 * element in the %multiset. Iteration is done in ascending order
336 * according to the keys.
337 */
338 iterator
339 end() const _GLIBCXX_NOEXCEPT
340 { return _M_t.end(); }
341
342 /**
343 * Returns a read-only (constant) reverse iterator that points to the
344 * last element in the %multiset. Iteration is done in descending order
345 * according to the keys.
346 */
347 reverse_iterator
348 rbegin() const _GLIBCXX_NOEXCEPT
349 { return _M_t.rbegin(); }
350
351 /**
352 * Returns a read-only (constant) reverse iterator that points to the
353 * last element in the %multiset. Iteration is done in descending order
354 * according to the keys.
355 */
356 reverse_iterator
357 rend() const _GLIBCXX_NOEXCEPT
358 { return _M_t.rend(); }
359
360 #if __cplusplus >= 201103L
361 /**
362 * Returns a read-only (constant) iterator that points to the first
363 * element in the %multiset. Iteration is done in ascending order
364 * according to the keys.
365 */
366 iterator
367 cbegin() const noexcept
368 { return _M_t.begin(); }
369
370 /**
371 * Returns a read-only (constant) iterator that points one past the last
372 * element in the %multiset. Iteration is done in ascending order
373 * according to the keys.
374 */
375 iterator
376 cend() const noexcept
377 { return _M_t.end(); }
378
379 /**
380 * Returns a read-only (constant) reverse iterator that points to the
381 * last element in the %multiset. Iteration is done in descending order
382 * according to the keys.
383 */
384 reverse_iterator
385 crbegin() const noexcept
386 { return _M_t.rbegin(); }
387
388 /**
389 * Returns a read-only (constant) reverse iterator that points to the
390 * last element in the %multiset. Iteration is done in descending order
391 * according to the keys.
392 */
393 reverse_iterator
394 crend() const noexcept
395 { return _M_t.rend(); }
396 #endif
397
398 /// Returns true if the %set is empty.
399 bool
400 empty() const _GLIBCXX_NOEXCEPT
401 { return _M_t.empty(); }
402
403 /// Returns the size of the %set.
404 size_type
405 size() const _GLIBCXX_NOEXCEPT
406 { return _M_t.size(); }
407
408 /// Returns the maximum size of the %set.
409 size_type
410 max_size() const _GLIBCXX_NOEXCEPT
411 { return _M_t.max_size(); }
412
413 /**
414 * @brief Swaps data with another %multiset.
415 * @param __x A %multiset of the same element and allocator types.
416 *
417 * This exchanges the elements between two multisets in constant time.
418 * (It is only swapping a pointer, an integer, and an instance of the @c
419 * Compare type (which itself is often stateless and empty), so it should
420 * be quite fast.)
421 * Note that the global std::swap() function is specialized such that
422 * std::swap(s1,s2) will feed to this function.
423 *
424 * Whether the allocators are swapped depends on the allocator traits.
425 */
426 void
427 swap(multiset& __x)
428 _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
429 { _M_t.swap(__x._M_t); }
430
431 // insert/erase
432 #if __cplusplus >= 201103L
433 /**
434 * @brief Builds and inserts an element into the %multiset.
435 * @param __args Arguments used to generate the element instance to be
436 * inserted.
437 * @return An iterator that points to the inserted element.
438 *
439 * This function inserts an element into the %multiset. Contrary
440 * to a std::set the %multiset does not rely on unique keys and thus
441 * multiple copies of the same element can be inserted.
442 *
443 * Insertion requires logarithmic time.
444 */
445 template<typename... _Args>
446 iterator
447 emplace(_Args&&... __args)
448 { return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); }
449
450 /**
451 * @brief Builds and inserts an element into the %multiset.
452 * @param __pos An iterator that serves as a hint as to where the
453 * element should be inserted.
454 * @param __args Arguments used to generate the element instance to be
455 * inserted.
456 * @return An iterator that points to the inserted element.
457 *
458 * This function inserts an element into the %multiset. Contrary
459 * to a std::set the %multiset does not rely on unique keys and thus
460 * multiple copies of the same element can be inserted.
461 *
462 * Note that the first parameter is only a hint and can potentially
463 * improve the performance of the insertion process. A bad hint would
464 * cause no gains in efficiency.
465 *
466 * See https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
467 * for more on @a hinting.
468 *
469 * Insertion requires logarithmic time (if the hint is not taken).
470 */
471 template<typename... _Args>
472 iterator
473 emplace_hint(const_iterator __pos, _Args&&... __args)
474 {
475 return _M_t._M_emplace_hint_equal(__pos,
476 std::forward<_Args>(__args)...);
477 }
478 #endif
479
480 /**
481 * @brief Inserts an element into the %multiset.
482 * @param __x Element to be inserted.
483 * @return An iterator that points to the inserted element.
484 *
485 * This function inserts an element into the %multiset. Contrary
486 * to a std::set the %multiset does not rely on unique keys and thus
487 * multiple copies of the same element can be inserted.
488 *
489 * Insertion requires logarithmic time.
490 */
491 iterator
492 insert(const value_type& __x)
493 { return _M_t._M_insert_equal(__x); }
494
495 #if __cplusplus >= 201103L
496 iterator
497 insert(value_type&& __x)
498 { return _M_t._M_insert_equal(std::move(__x)); }
499 #endif
500
501 /**
502 * @brief Inserts an element into the %multiset.
503 * @param __position An iterator that serves as a hint as to where the
504 * element should be inserted.
505 * @param __x Element to be inserted.
506 * @return An iterator that points to the inserted element.
507 *
508 * This function inserts an element into the %multiset. Contrary
509 * to a std::set the %multiset does not rely on unique keys and thus
510 * multiple copies of the same element can be inserted.
511 *
512 * Note that the first parameter is only a hint and can potentially
513 * improve the performance of the insertion process. A bad hint would
514 * cause no gains in efficiency.
515 *
516 * See https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
517 * for more on @a hinting.
518 *
519 * Insertion requires logarithmic time (if the hint is not taken).
520 */
521 iterator
522 insert(const_iterator __position, const value_type& __x)
523 { return _M_t._M_insert_equal_(__position, __x); }
524
525 #if __cplusplus >= 201103L
526 iterator
527 insert(const_iterator __position, value_type&& __x)
528 { return _M_t._M_insert_equal_(__position, std::move(__x)); }
529 #endif
530
531 /**
532 * @brief A template function that tries to insert a range of elements.
533 * @param __first Iterator pointing to the start of the range to be
534 * inserted.
535 * @param __last Iterator pointing to the end of the range.
536 *
537 * Complexity similar to that of the range constructor.
538 */
539 template<typename _InputIterator>
540 void
541 insert(_InputIterator __first, _InputIterator __last)
542 { _M_t._M_insert_equal(__first, __last); }
543
544 #if __cplusplus >= 201103L
545 /**
546 * @brief Attempts to insert a list of elements into the %multiset.
547 * @param __l A std::initializer_list<value_type> of elements
548 * to be inserted.
549 *
550 * Complexity similar to that of the range constructor.
551 */
552 void
553 insert(initializer_list<value_type> __l)
554 { this->insert(__l.begin(), __l.end()); }
555 #endif
556
557 #if __cplusplus > 201402L
558 /// Extract a node.
559 node_type
560 extract(const_iterator __pos)
561 {
562 __glibcxx_assert(__pos != end());
563 return _M_t.extract(__pos);
564 }
565
566 /// Extract a node.
567 node_type
568 extract(const key_type& __x)
569 { return _M_t.extract(__x); }
570
571 /// Re-insert an extracted node.
572 iterator
573 insert(node_type&& __nh)
574 { return _M_t._M_reinsert_node_equal(std::move(__nh)); }
575
576 /// Re-insert an extracted node.
577 iterator
578 insert(const_iterator __hint, node_type&& __nh)
579 { return _M_t._M_reinsert_node_hint_equal(__hint, std::move(__nh)); }
580
581 template<typename, typename>
582 friend class _Rb_tree_merge_helper;
583
584 template<typename _Compare1>
585 void
586 merge(multiset<_Key, _Compare1, _Alloc>& __source)
587 {
588 using _Merge_helper = _Rb_tree_merge_helper<multiset, _Compare1>;
589 _M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source));
590 }
591
592 template<typename _Compare1>
593 void
594 merge(multiset<_Key, _Compare1, _Alloc>&& __source)
595 { merge(__source); }
596
597 template<typename _Compare1>
598 void
599 merge(set<_Key, _Compare1, _Alloc>& __source)
600 {
601 using _Merge_helper = _Rb_tree_merge_helper<multiset, _Compare1>;
602 _M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source));
603 }
604
605 template<typename _Compare1>
606 void
607 merge(set<_Key, _Compare1, _Alloc>&& __source)
608 { merge(__source); }
609 #endif // C++17
610
611 #if __cplusplus >= 201103L
612 // _GLIBCXX_RESOLVE_LIB_DEFECTS
613 // DR 130. Associative erase should return an iterator.
614 /**
615 * @brief Erases an element from a %multiset.
616 * @param __position An iterator pointing to the element to be erased.
617 * @return An iterator pointing to the element immediately following
618 * @a position prior to the element being erased. If no such
619 * element exists, end() is returned.
620 *
621 * This function erases an element, pointed to by the given iterator,
622 * from a %multiset. Note that this function only erases the element,
623 * and that if the element is itself a pointer, the pointed-to memory is
624 * not touched in any way. Managing the pointer is the user's
625 * responsibility.
626 */
627 _GLIBCXX_ABI_TAG_CXX11
628 iterator
629 erase(const_iterator __position)
630 { return _M_t.erase(__position); }
631 #else
632 /**
633 * @brief Erases an element from a %multiset.
634 * @param __position An iterator pointing to the element to be erased.
635 *
636 * This function erases an element, pointed to by the given iterator,
637 * from a %multiset. Note that this function only erases the element,
638 * and that if the element is itself a pointer, the pointed-to memory is
639 * not touched in any way. Managing the pointer is the user's
640 * responsibility.
641 */
642 void
643 erase(iterator __position)
644 { _M_t.erase(__position); }
645 #endif
646
647 /**
648 * @brief Erases elements according to the provided key.
649 * @param __x Key of element to be erased.
650 * @return The number of elements erased.
651 *
652 * This function erases all elements located by the given key from a
653 * %multiset.
654 * Note that this function only erases the element, and that if
655 * the element is itself a pointer, the pointed-to memory is not touched
656 * in any way. Managing the pointer is the user's responsibility.
657 */
658 size_type
659 erase(const key_type& __x)
660 { return _M_t.erase(__x); }
661
662 #if __cplusplus >= 201103L
663 // _GLIBCXX_RESOLVE_LIB_DEFECTS
664 // DR 130. Associative erase should return an iterator.
665 /**
666 * @brief Erases a [first,last) range of elements from a %multiset.
667 * @param __first Iterator pointing to the start of the range to be
668 * erased.
669 * @param __last Iterator pointing to the end of the range to
670 * be erased.
671 * @return The iterator @a last.
672 *
673 * This function erases a sequence of elements from a %multiset.
674 * Note that this function only erases the elements, and that if
675 * the elements themselves are pointers, the pointed-to memory is not
676 * touched in any way. Managing the pointer is the user's
677 * responsibility.
678 */
679 _GLIBCXX_ABI_TAG_CXX11
680 iterator
681 erase(const_iterator __first, const_iterator __last)
682 { return _M_t.erase(__first, __last); }
683 #else
684 /**
685 * @brief Erases a [first,last) range of elements from a %multiset.
686 * @param first Iterator pointing to the start of the range to be
687 * erased.
688 * @param last Iterator pointing to the end of the range to be erased.
689 *
690 * This function erases a sequence of elements from a %multiset.
691 * Note that this function only erases the elements, and that if
692 * the elements themselves are pointers, the pointed-to memory is not
693 * touched in any way. Managing the pointer is the user's
694 * responsibility.
695 */
696 void
697 erase(iterator __first, iterator __last)
698 { _M_t.erase(__first, __last); }
699 #endif
700
701 /**
702 * Erases all elements in a %multiset. Note that this function only
703 * erases the elements, and that if the elements themselves are pointers,
704 * the pointed-to memory is not touched in any way. Managing the pointer
705 * is the user's responsibility.
706 */
707 void
708 clear() _GLIBCXX_NOEXCEPT
709 { _M_t.clear(); }
710
711 // multiset operations:
712
713 //@{
714 /**
715 * @brief Finds the number of elements with given key.
716 * @param __x Key of elements to be located.
717 * @return Number of elements with specified key.
718 */
719 size_type
720 count(const key_type& __x) const
721 { return _M_t.count(__x); }
722
723 #if __cplusplus > 201103L
724 template<typename _Kt>
725 auto
726 count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
727 { return _M_t._M_count_tr(__x); }
728 #endif
729 //@}
730
731 // _GLIBCXX_RESOLVE_LIB_DEFECTS
732 // 214. set::find() missing const overload
733 //@{
734 /**
735 * @brief Tries to locate an element in a %set.
736 * @param __x Element to be located.
737 * @return Iterator pointing to sought-after element, or end() if not
738 * found.
739 *
740 * This function takes a key and tries to locate the element with which
741 * the key matches. If successful the function returns an iterator
742 * pointing to the sought after element. If unsuccessful it returns the
743 * past-the-end ( @c end() ) iterator.
744 */
745 iterator
746 find(const key_type& __x)
747 { return _M_t.find(__x); }
748
749 const_iterator
750 find(const key_type& __x) const
751 { return _M_t.find(__x); }
752
753 #if __cplusplus > 201103L
754 template<typename _Kt>
755 auto
756 find(const _Kt& __x)
757 -> decltype(iterator{_M_t._M_find_tr(__x)})
758 { return iterator{_M_t._M_find_tr(__x)}; }
759
760 template<typename _Kt>
761 auto
762 find(const _Kt& __x) const
763 -> decltype(const_iterator{_M_t._M_find_tr(__x)})
764 { return const_iterator{_M_t._M_find_tr(__x)}; }
765 #endif
766 //@}
767
768 //@{
769 /**
770 * @brief Finds the beginning of a subsequence matching given key.
771 * @param __x Key to be located.
772 * @return Iterator pointing to first element equal to or greater
773 * than key, or end().
774 *
775 * This function returns the first element of a subsequence of elements
776 * that matches the given key. If unsuccessful it returns an iterator
777 * pointing to the first element that has a greater value than given key
778 * or end() if no such element exists.
779 */
780 iterator
781 lower_bound(const key_type& __x)
782 { return _M_t.lower_bound(__x); }
783
784 const_iterator
785 lower_bound(const key_type& __x) const
786 { return _M_t.lower_bound(__x); }
787
788 #if __cplusplus > 201103L
789 template<typename _Kt>
790 auto
791 lower_bound(const _Kt& __x)
792 -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
793 { return iterator(_M_t._M_lower_bound_tr(__x)); }
794
795 template<typename _Kt>
796 auto
797 lower_bound(const _Kt& __x) const
798 -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
799 { return iterator(_M_t._M_lower_bound_tr(__x)); }
800 #endif
801 //@}
802
803 //@{
804 /**
805 * @brief Finds the end of a subsequence matching given key.
806 * @param __x Key to be located.
807 * @return Iterator pointing to the first element
808 * greater than key, or end().
809 */
810 iterator
811 upper_bound(const key_type& __x)
812 { return _M_t.upper_bound(__x); }
813
814 const_iterator
815 upper_bound(const key_type& __x) const
816 { return _M_t.upper_bound(__x); }
817
818 #if __cplusplus > 201103L
819 template<typename _Kt>
820 auto
821 upper_bound(const _Kt& __x)
822 -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
823 { return iterator(_M_t._M_upper_bound_tr(__x)); }
824
825 template<typename _Kt>
826 auto
827 upper_bound(const _Kt& __x) const
828 -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
829 { return iterator(_M_t._M_upper_bound_tr(__x)); }
830 #endif
831 //@}
832
833 //@{
834 /**
835 * @brief Finds a subsequence matching given key.
836 * @param __x Key to be located.
837 * @return Pair of iterators that possibly points to the subsequence
838 * matching given key.
839 *
840 * This function is equivalent to
841 * @code
842 * std::make_pair(c.lower_bound(val),
843 * c.upper_bound(val))
844 * @endcode
845 * (but is faster than making the calls separately).
846 *
847 * This function probably only makes sense for multisets.
848 */
849 std::pair<iterator, iterator>
850 equal_range(const key_type& __x)
851 { return _M_t.equal_range(__x); }
852
853 std::pair<const_iterator, const_iterator>
854 equal_range(const key_type& __x) const
855 { return _M_t.equal_range(__x); }
856
857 #if __cplusplus > 201103L
858 template<typename _Kt>
859 auto
860 equal_range(const _Kt& __x)
861 -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
862 { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
863
864 template<typename _Kt>
865 auto
866 equal_range(const _Kt& __x) const
867 -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
868 { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
869 #endif
870 //@}
871
872 template<typename _K1, typename _C1, typename _A1>
873 friend bool
874 operator==(const multiset<_K1, _C1, _A1>&,
875 const multiset<_K1, _C1, _A1>&);
876
877 template<typename _K1, typename _C1, typename _A1>
878 friend bool
879 operator< (const multiset<_K1, _C1, _A1>&,
880 const multiset<_K1, _C1, _A1>&);
881 };
882
883 /**
884 * @brief Multiset equality comparison.
885 * @param __x A %multiset.
886 * @param __y A %multiset of the same type as @a __x.
887 * @return True iff the size and elements of the multisets are equal.
888 *
889 * This is an equivalence relation. It is linear in the size of the
890 * multisets.
891 * Multisets are considered equivalent if their sizes are equal, and if
892 * corresponding elements compare equal.
893 */
894 template<typename _Key, typename _Compare, typename _Alloc>
895 inline bool
896 operator==(const multiset<_Key, _Compare, _Alloc>& __x,
897 const multiset<_Key, _Compare, _Alloc>& __y)
898 { return __x._M_t == __y._M_t; }
899
900 /**
901 * @brief Multiset ordering relation.
902 * @param __x A %multiset.
903 * @param __y A %multiset of the same type as @a __x.
904 * @return True iff @a __x is lexicographically less than @a __y.
905 *
906 * This is a total ordering relation. It is linear in the size of the
907 * sets. The elements must be comparable with @c <.
908 *
909 * See std::lexicographical_compare() for how the determination is made.
910 */
911 template<typename _Key, typename _Compare, typename _Alloc>
912 inline bool
913 operator<(const multiset<_Key, _Compare, _Alloc>& __x,
914 const multiset<_Key, _Compare, _Alloc>& __y)
915 { return __x._M_t < __y._M_t; }
916
917 /// Returns !(x == y).
918 template<typename _Key, typename _Compare, typename _Alloc>
919 inline bool
920 operator!=(const multiset<_Key, _Compare, _Alloc>& __x,
921 const multiset<_Key, _Compare, _Alloc>& __y)
922 { return !(__x == __y); }
923
924 /// Returns y < x.
925 template<typename _Key, typename _Compare, typename _Alloc>
926 inline bool
927 operator>(const multiset<_Key,_Compare,_Alloc>& __x,
928 const multiset<_Key,_Compare,_Alloc>& __y)
929 { return __y < __x; }
930
931 /// Returns !(y < x)
932 template<typename _Key, typename _Compare, typename _Alloc>
933 inline bool
934 operator<=(const multiset<_Key, _Compare, _Alloc>& __x,
935 const multiset<_Key, _Compare, _Alloc>& __y)
936 { return !(__y < __x); }
937
938 /// Returns !(x < y)
939 template<typename _Key, typename _Compare, typename _Alloc>
940 inline bool
941 operator>=(const multiset<_Key, _Compare, _Alloc>& __x,
942 const multiset<_Key, _Compare, _Alloc>& __y)
943 { return !(__x < __y); }
944
945 /// See std::multiset::swap().
946 template<typename _Key, typename _Compare, typename _Alloc>
947 inline void
948 swap(multiset<_Key, _Compare, _Alloc>& __x,
949 multiset<_Key, _Compare, _Alloc>& __y)
950 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
951 { __x.swap(__y); }
952
953 _GLIBCXX_END_NAMESPACE_CONTAINER
954
955 #if __cplusplus > 201402L
956 _GLIBCXX_BEGIN_NAMESPACE_VERSION
957 // Allow std::multiset access to internals of compatible sets.
958 template<typename _Val, typename _Cmp1, typename _Alloc, typename _Cmp2>
959 struct
960 _Rb_tree_merge_helper<_GLIBCXX_STD_C::multiset<_Val, _Cmp1, _Alloc>,
961 _Cmp2>
962 {
963 private:
964 friend class _GLIBCXX_STD_C::multiset<_Val, _Cmp1, _Alloc>;
965
966 static auto&
967 _S_get_tree(_GLIBCXX_STD_C::set<_Val, _Cmp2, _Alloc>& __set)
968 { return __set._M_t; }
969
970 static auto&
971 _S_get_tree(_GLIBCXX_STD_C::multiset<_Val, _Cmp2, _Alloc>& __set)
972 { return __set._M_t; }
973 };
974 _GLIBCXX_END_NAMESPACE_VERSION
975 #endif // C++17
976
977 } // namespace std
978
979 #endif /* _STL_MULTISET_H */
980