1// Set implementation -*- C++ -*-
2
3// Copyright (C) 2001-2016 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_set.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_SET_H
57#define _STL_SET_H 1
58
59#include <bits/concept_check.h>
60#if __cplusplus >= 201103L
61#include <initializer_list>
62#endif
63
64namespace std _GLIBCXX_VISIBILITY(default)
65{
66_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
67
68 /**
69 * @brief A standard container made up of unique keys, which can be
70 * retrieved in logarithmic time.
71 *
72 * @ingroup associative_containers
73 *
74 * @tparam _Key Type of key objects.
75 * @tparam _Compare Comparison function object type, defaults to less<_Key>.
76 * @tparam _Alloc Allocator type, defaults to allocator<_Key>.
77 *
78 * Meets the requirements of a <a href="tables.html#65">container</a>, a
79 * <a href="tables.html#66">reversible container</a>, and an
80 * <a href="tables.html#69">associative container</a> (using unique keys).
81 *
82 * Sets support bidirectional iterators.
83 *
84 * The private tree data is declared exactly the same way for set and
85 * multiset; the distinction is made entirely in how the tree functions are
86 * called (*_unique versus *_equal, same as the standard).
87 */
88 template<typename _Key, typename _Compare = std::less<_Key>,
89 typename _Alloc = std::allocator<_Key> >
90 class set
91 {
92 // concept requirements
93 typedef typename _Alloc::value_type _Alloc_value_type;
94 __glibcxx_class_requires(_Key, _SGIAssignableConcept)
95 __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
96 _BinaryFunctionConcept)
97 __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept)
98
99 public:
100 // typedefs:
101 //@{
102 /// Public typedefs.
103 typedef _Key key_type;
104 typedef _Key value_type;
105 typedef _Compare key_compare;
106 typedef _Compare value_compare;
107 typedef _Alloc allocator_type;
108 //@}
109
110 private:
111 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
112 rebind<_Key>::other _Key_alloc_type;
113
114 typedef _Rb_tree<key_type, value_type, _Identity<value_type>,
115 key_compare, _Key_alloc_type> _Rep_type;
116 _Rep_type _M_t; // Red-black tree representing set.
117
118 typedef __gnu_cxx::__alloc_traits<_Key_alloc_type> _Alloc_traits;
119
120 public:
121 //@{
122 /// Iterator-related typedefs.
123 typedef typename _Alloc_traits::pointer pointer;
124 typedef typename _Alloc_traits::const_pointer const_pointer;
125 typedef typename _Alloc_traits::reference reference;
126 typedef typename _Alloc_traits::const_reference const_reference;
127 // _GLIBCXX_RESOLVE_LIB_DEFECTS
128 // DR 103. set::iterator is required to be modifiable,
129 // but this allows modification of keys.
130 typedef typename _Rep_type::const_iterator iterator;
131 typedef typename _Rep_type::const_iterator const_iterator;
132 typedef typename _Rep_type::const_reverse_iterator reverse_iterator;
133 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
134 typedef typename _Rep_type::size_type size_type;
135 typedef typename _Rep_type::difference_type difference_type;
136 //@}
137
138 // allocation/deallocation
139 /**
140 * @brief Default constructor creates no elements.
141 */
142 set()
143#if __cplusplus >= 201103L
144 noexcept(is_nothrow_default_constructible<allocator_type>::value)
145#endif
146 : _M_t() { }
147
148 /**
149 * @brief Creates a %set with no elements.
150 * @param __comp Comparator to use.
151 * @param __a An allocator object.
152 */
153 explicit
154 set(const _Compare& __comp,
155 const allocator_type& __a = allocator_type())
156 : _M_t(__comp, _Key_alloc_type(__a)) { }
157
158 /**
159 * @brief Builds a %set from a range.
160 * @param __first An input iterator.
161 * @param __last An input iterator.
162 *
163 * Create a %set consisting of copies of the elements from
164 * [__first,__last). This is linear in N if the range is
165 * already sorted, and NlogN otherwise (where N is
166 * distance(__first,__last)).
167 */
168 template<typename _InputIterator>
169 set(_InputIterator __first, _InputIterator __last)
170 : _M_t()
171 { _M_t._M_insert_unique(__first, __last); }
172
173 /**
174 * @brief Builds a %set from a range.
175 * @param __first An input iterator.
176 * @param __last An input iterator.
177 * @param __comp A comparison functor.
178 * @param __a An allocator object.
179 *
180 * Create a %set consisting of copies of the elements from
181 * [__first,__last). This is linear in N if the range is
182 * already sorted, and NlogN otherwise (where N is
183 * distance(__first,__last)).
184 */
185 template<typename _InputIterator>
186 set(_InputIterator __first, _InputIterator __last,
187 const _Compare& __comp,
188 const allocator_type& __a = allocator_type())
189 : _M_t(__comp, _Key_alloc_type(__a))
190 { _M_t._M_insert_unique(__first, __last); }
191
192 /**
193 * @brief %Set copy constructor.
194 * @param __x A %set of identical element and allocator types.
195 *
196 * The newly-created %set uses a copy of the allocation object used
197 * by @a __x.
198 */
199 set(const set& __x)
200 : _M_t(__x._M_t) { }
201
202#if __cplusplus >= 201103L
203 /**
204 * @brief %Set move constructor
205 * @param __x A %set of identical element and allocator types.
206 *
207 * The newly-created %set contains the exact contents of @a x.
208 * The contents of @a x are a valid, but unspecified %set.
209 */
210 set(set&& __x)
211 noexcept(is_nothrow_copy_constructible<_Compare>::value)
212 : _M_t(std::move(__x._M_t)) { }
213
214 /**
215 * @brief Builds a %set from an initializer_list.
216 * @param __l An initializer_list.
217 * @param __comp A comparison functor.
218 * @param __a An allocator object.
219 *
220 * Create a %set consisting of copies of the elements in the list.
221 * This is linear in N if the list is already sorted, and NlogN
222 * otherwise (where N is @a __l.size()).
223 */
224 set(initializer_list<value_type> __l,
225 const _Compare& __comp = _Compare(),
226 const allocator_type& __a = allocator_type())
227 : _M_t(__comp, _Key_alloc_type(__a))
228 { _M_t._M_insert_unique(__l.begin(), __l.end()); }
229
230 /// Allocator-extended default constructor.
231 explicit
232 set(const allocator_type& __a)
233 : _M_t(_Compare(), _Key_alloc_type(__a)) { }
234
235 /// Allocator-extended copy constructor.
236 set(const set& __x, const allocator_type& __a)
237 : _M_t(__x._M_t, _Key_alloc_type(__a)) { }
238
239 /// Allocator-extended move constructor.
240 set(set&& __x, const allocator_type& __a)
241 noexcept(is_nothrow_copy_constructible<_Compare>::value
242 && _Alloc_traits::_S_always_equal())
243 : _M_t(std::move(__x._M_t), _Key_alloc_type(__a)) { }
244
245 /// Allocator-extended initialier-list constructor.
246 set(initializer_list<value_type> __l, const allocator_type& __a)
247 : _M_t(_Compare(), _Key_alloc_type(__a))
248 { _M_t._M_insert_unique(__l.begin(), __l.end()); }
249
250 /// Allocator-extended range constructor.
251 template<typename _InputIterator>
252 set(_InputIterator __first, _InputIterator __last,
253 const allocator_type& __a)
254 : _M_t(_Compare(), _Key_alloc_type(__a))
255 { _M_t._M_insert_unique(__first, __last); }
256#endif
257
258 /**
259 * @brief %Set assignment operator.
260 * @param __x A %set of identical element and allocator types.
261 *
262 * All the elements of @a __x are copied, but unlike the copy
263 * constructor, the allocator object is not copied.
264 */
265 set&
266 operator=(const set& __x)
267 {
268 _M_t = __x._M_t;
269 return *this;
270 }
271
272#if __cplusplus >= 201103L
273 /// Move assignment operator.
274 set&
275 operator=(set&&) = default;
276
277 /**
278 * @brief %Set list assignment operator.
279 * @param __l An initializer_list.
280 *
281 * This function fills a %set with copies of the elements in the
282 * initializer list @a __l.
283 *
284 * Note that the assignment completely changes the %set and
285 * that the resulting %set's size is the same as the number
286 * of elements assigned. Old data may be lost.
287 */
288 set&
289 operator=(initializer_list<value_type> __l)
290 {
291 _M_t._M_assign_unique(__l.begin(), __l.end());
292 return *this;
293 }
294#endif
295
296 // accessors:
297
298 /// Returns the comparison object with which the %set was constructed.
299 key_compare
300 key_comp() const
301 { return _M_t.key_comp(); }
302 /// Returns the comparison object with which the %set was constructed.
303 value_compare
304 value_comp() const
305 { return _M_t.key_comp(); }
306 /// Returns the allocator object with which the %set was constructed.
307 allocator_type
308 get_allocator() const _GLIBCXX_NOEXCEPT
309 { return allocator_type(_M_t.get_allocator()); }
310
311 /**
312 * Returns a read-only (constant) iterator that points to the first
313 * element in the %set. Iteration is done in ascending order according
314 * to the keys.
315 */
316 iterator
317 begin() const _GLIBCXX_NOEXCEPT
318 { return _M_t.begin(); }
319
320 /**
321 * Returns a read-only (constant) iterator that points one past the last
322 * element in the %set. Iteration is done in ascending order according
323 * to the keys.
324 */
325 iterator
326 end() const _GLIBCXX_NOEXCEPT
327 { return _M_t.end(); }
328
329 /**
330 * Returns a read-only (constant) iterator that points to the last
331 * element in the %set. Iteration is done in descending order according
332 * to the keys.
333 */
334 reverse_iterator
335 rbegin() const _GLIBCXX_NOEXCEPT
336 { return _M_t.rbegin(); }
337
338 /**
339 * Returns a read-only (constant) reverse iterator that points to the
340 * last pair in the %set. Iteration is done in descending order
341 * according to the keys.
342 */
343 reverse_iterator
344 rend() const _GLIBCXX_NOEXCEPT
345 { return _M_t.rend(); }
346
347#if __cplusplus >= 201103L
348 /**
349 * Returns a read-only (constant) iterator that points to the first
350 * element in the %set. Iteration is done in ascending order according
351 * to the keys.
352 */
353 iterator
354 cbegin() const noexcept
355 { return _M_t.begin(); }
356
357 /**
358 * Returns a read-only (constant) iterator that points one past the last
359 * element in the %set. Iteration is done in ascending order according
360 * to the keys.
361 */
362 iterator
363 cend() const noexcept
364 { return _M_t.end(); }
365
366 /**
367 * Returns a read-only (constant) iterator that points to the last
368 * element in the %set. Iteration is done in descending order according
369 * to the keys.
370 */
371 reverse_iterator
372 crbegin() const noexcept
373 { return _M_t.rbegin(); }
374
375 /**
376 * Returns a read-only (constant) reverse iterator that points to the
377 * last pair in the %set. Iteration is done in descending order
378 * according to the keys.
379 */
380 reverse_iterator
381 crend() const noexcept
382 { return _M_t.rend(); }
383#endif
384
385 /// Returns true if the %set is empty.
386 bool
387 empty() const _GLIBCXX_NOEXCEPT
388 { return _M_t.empty(); }
389
390 /// Returns the size of the %set.
391 size_type
392 size() const _GLIBCXX_NOEXCEPT
393 { return _M_t.size(); }
394
395 /// Returns the maximum size of the %set.
396 size_type
397 max_size() const _GLIBCXX_NOEXCEPT
398 { return _M_t.max_size(); }
399
400 /**
401 * @brief Swaps data with another %set.
402 * @param __x A %set of the same element and allocator types.
403 *
404 * This exchanges the elements between two sets in constant
405 * time. (It is only swapping a pointer, an integer, and an
406 * instance of the @c Compare type (which itself is often
407 * stateless and empty), so it should be quite fast.) Note
408 * that the global std::swap() function is specialized such
409 * that std::swap(s1,s2) will feed to this function.
410 */
411 void
412 swap(set& __x)
413 _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
414 { _M_t.swap(__x._M_t); }
415
416 // insert/erase
417#if __cplusplus >= 201103L
418 /**
419 * @brief Attempts to build and insert an element into the %set.
420 * @param __args Arguments used to generate an element.
421 * @return A pair, of which the first element is an iterator that points
422 * to the possibly inserted element, and the second is a bool
423 * that is true if the element was actually inserted.
424 *
425 * This function attempts to build and insert an element into the %set.
426 * A %set relies on unique keys and thus an element is only inserted if
427 * it is not already present in the %set.
428 *
429 * Insertion requires logarithmic time.
430 */
431 template<typename... _Args>
432 std::pair<iterator, bool>
433 emplace(_Args&&... __args)
434 { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
435
436 /**
437 * @brief Attempts to insert an element into the %set.
438 * @param __pos An iterator that serves as a hint as to where the
439 * element should be inserted.
440 * @param __args Arguments used to generate the element to be
441 * inserted.
442 * @return An iterator that points to the element with key equivalent to
443 * the one generated from @a __args (may or may not be the
444 * element itself).
445 *
446 * This function is not concerned about whether the insertion took place,
447 * and thus does not return a boolean like the single-argument emplace()
448 * does. Note that the first parameter is only a hint and can
449 * potentially improve the performance of the insertion process. A bad
450 * hint would cause no gains in efficiency.
451 *
452 * For more on @a hinting, see:
453 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
454 *
455 * Insertion requires logarithmic time (if the hint is not taken).
456 */
457 template<typename... _Args>
458 iterator
459 emplace_hint(const_iterator __pos, _Args&&... __args)
460 {
461 return _M_t._M_emplace_hint_unique(__pos,
462 std::forward<_Args>(__args)...);
463 }
464#endif
465
466 /**
467 * @brief Attempts to insert an element into the %set.
468 * @param __x Element to be inserted.
469 * @return A pair, of which the first element is an iterator that points
470 * to the possibly inserted element, and the second is a bool
471 * that is true if the element was actually inserted.
472 *
473 * This function attempts to insert an element into the %set. A %set
474 * relies on unique keys and thus an element is only inserted if it is
475 * not already present in the %set.
476 *
477 * Insertion requires logarithmic time.
478 */
479 std::pair<iterator, bool>
480 insert(const value_type& __x)
481 {
482 std::pair<typename _Rep_type::iterator, bool> __p =
483 _M_t._M_insert_unique(__x);
484 return std::pair<iterator, bool>(__p.first, __p.second);
485 }
486
487#if __cplusplus >= 201103L
488 std::pair<iterator, bool>
489 insert(value_type&& __x)
490 {
491 std::pair<typename _Rep_type::iterator, bool> __p =
492 _M_t._M_insert_unique(std::move(__x));
493 return std::pair<iterator, bool>(__p.first, __p.second);
494 }
495#endif
496
497 /**
498 * @brief Attempts to insert an element into the %set.
499 * @param __position An iterator that serves as a hint as to where the
500 * element should be inserted.
501 * @param __x Element to be inserted.
502 * @return An iterator that points to the element with key of
503 * @a __x (may or may not be the element passed in).
504 *
505 * This function is not concerned about whether the insertion took place,
506 * and thus does not return a boolean like the single-argument insert()
507 * does. Note that the first parameter is only a hint and can
508 * potentially improve the performance of the insertion process. A bad
509 * hint would cause no gains in efficiency.
510 *
511 * For more on @a hinting, see:
512 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
513 *
514 * Insertion requires logarithmic time (if the hint is not taken).
515 */
516 iterator
517 insert(const_iterator __position, const value_type& __x)
518 { return _M_t._M_insert_unique_(__position, __x); }
519
520#if __cplusplus >= 201103L
521 iterator
522 insert(const_iterator __position, value_type&& __x)
523 { return _M_t._M_insert_unique_(__position, std::move(__x)); }
524#endif
525
526 /**
527 * @brief A template function that attempts to insert a range
528 * of elements.
529 * @param __first Iterator pointing to the start of the range to be
530 * inserted.
531 * @param __last Iterator pointing to the end of the range.
532 *
533 * Complexity similar to that of the range constructor.
534 */
535 template<typename _InputIterator>
536 void
537 insert(_InputIterator __first, _InputIterator __last)
538 { _M_t._M_insert_unique(__first, __last); }
539
540#if __cplusplus >= 201103L
541 /**
542 * @brief Attempts to insert a list of elements into the %set.
543 * @param __l A std::initializer_list<value_type> of elements
544 * to be inserted.
545 *
546 * Complexity similar to that of the range constructor.
547 */
548 void
549 insert(initializer_list<value_type> __l)
550 { this->insert(__l.begin(), __l.end()); }
551#endif
552
553#if __cplusplus >= 201103L
554 // _GLIBCXX_RESOLVE_LIB_DEFECTS
555 // DR 130. Associative erase should return an iterator.
556 /**
557 * @brief Erases an element from a %set.
558 * @param __position An iterator pointing to the element to be erased.
559 * @return An iterator pointing to the element immediately following
560 * @a __position prior to the element being erased. If no such
561 * element exists, end() is returned.
562 *
563 * This function erases an element, pointed to by the given iterator,
564 * from a %set. Note that this function only erases the element, and
565 * that if the element is itself a pointer, the pointed-to memory is not
566 * touched in any way. Managing the pointer is the user's
567 * responsibility.
568 */
569 _GLIBCXX_ABI_TAG_CXX11
570 iterator
571 erase(const_iterator __position)
572 { return _M_t.erase(__position); }
573#else
574 /**
575 * @brief Erases an element from a %set.
576 * @param position An iterator pointing to the element to be erased.
577 *
578 * This function erases an element, pointed to by the given iterator,
579 * from a %set. Note that this function only erases the element, and
580 * that if the element is itself a pointer, the pointed-to memory is not
581 * touched in any way. Managing the pointer is the user's
582 * responsibility.
583 */
584 void
585 erase(iterator __position)
586 { _M_t.erase(__position); }
587#endif
588
589 /**
590 * @brief Erases elements according to the provided key.
591 * @param __x Key of element to be erased.
592 * @return The number of elements erased.
593 *
594 * This function erases all the elements located by the given key from
595 * a %set.
596 * Note that this function only erases the element, and that if
597 * the element is itself a pointer, the pointed-to memory is not touched
598 * in any way. Managing the pointer is the user's responsibility.
599 */
600 size_type
601 erase(const key_type& __x)
602 { return _M_t.erase(__x); }
603
604#if __cplusplus >= 201103L
605 // _GLIBCXX_RESOLVE_LIB_DEFECTS
606 // DR 130. Associative erase should return an iterator.
607 /**
608 * @brief Erases a [__first,__last) range of elements from a %set.
609 * @param __first Iterator pointing to the start of the range to be
610 * erased.
611
612 * @param __last Iterator pointing to the end of the range to
613 * be erased.
614 * @return The iterator @a __last.
615 *
616 * This function erases a sequence of elements from a %set.
617 * Note that this function only erases the element, and that if
618 * the element is itself a pointer, the pointed-to memory is not touched
619 * in any way. Managing the pointer is the user's responsibility.
620 */
621 _GLIBCXX_ABI_TAG_CXX11
622 iterator
623 erase(const_iterator __first, const_iterator __last)
624 { return _M_t.erase(__first, __last); }
625#else
626 /**
627 * @brief Erases a [first,last) range of elements from a %set.
628 * @param __first Iterator pointing to the start of the range to be
629 * erased.
630 * @param __last Iterator pointing to the end of the range to
631 * be erased.
632 *
633 * This function erases a sequence of elements from a %set.
634 * Note that this function only erases the element, and that if
635 * the element is itself a pointer, the pointed-to memory is not touched
636 * in any way. Managing the pointer is the user's responsibility.
637 */
638 void
639 erase(iterator __first, iterator __last)
640 { _M_t.erase(__first, __last); }
641#endif
642
643 /**
644 * Erases all elements in a %set. Note that this function only erases
645 * the elements, and that if the elements themselves are pointers, the
646 * pointed-to memory is not touched in any way. Managing the pointer is
647 * the user's responsibility.
648 */
649 void
650 clear() _GLIBCXX_NOEXCEPT
651 { _M_t.clear(); }
652
653 // set operations:
654
655 //@{
656 /**
657 * @brief Finds the number of elements.
658 * @param __x Element to located.
659 * @return Number of elements with specified key.
660 *
661 * This function only makes sense for multisets; for set the result will
662 * either be 0 (not present) or 1 (present).
663 */
664 size_type
665 count(const key_type& __x) const
666 { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
667
668#if __cplusplus > 201103L
669 template<typename _Kt>
670 auto
671 count(const _Kt& __x) const
672 -> decltype(_M_t._M_count_tr(__x))
673 { return _M_t._M_find_tr(__x) == _M_t.end() ? 0 : 1; }
674#endif
675 //@}
676
677 // _GLIBCXX_RESOLVE_LIB_DEFECTS
678 // 214. set::find() missing const overload
679 //@{
680 /**
681 * @brief Tries to locate an element in a %set.
682 * @param __x Element to be located.
683 * @return Iterator pointing to sought-after element, or end() if not
684 * found.
685 *
686 * This function takes a key and tries to locate the element with which
687 * the key matches. If successful the function returns an iterator
688 * pointing to the sought after element. If unsuccessful it returns the
689 * past-the-end ( @c end() ) iterator.
690 */
691 iterator
692 find(const key_type& __x)
693 { return _M_t.find(__x); }
694
695 const_iterator
696 find(const key_type& __x) const
697 { return _M_t.find(__x); }
698
699#if __cplusplus > 201103L
700 template<typename _Kt>
701 auto
702 find(const _Kt& __x)
703 -> decltype(iterator{_M_t._M_find_tr(__x)})
704 { return iterator{_M_t._M_find_tr(__x)}; }
705
706 template<typename _Kt>
707 auto
708 find(const _Kt& __x) const
709 -> decltype(const_iterator{_M_t._M_find_tr(__x)})
710 { return const_iterator{_M_t._M_find_tr(__x)}; }
711#endif
712 //@}
713
714 //@{
715 /**
716 * @brief Finds the beginning of a subsequence matching given key.
717 * @param __x Key to be located.
718 * @return Iterator pointing to first element equal to or greater
719 * than key, or end().
720 *
721 * This function returns the first element of a subsequence of elements
722 * that matches the given key. If unsuccessful it returns an iterator
723 * pointing to the first element that has a greater value than given key
724 * or end() if no such element exists.
725 */
726 iterator
727 lower_bound(const key_type& __x)
728 { return _M_t.lower_bound(__x); }
729
730 const_iterator
731 lower_bound(const key_type& __x) const
732 { return _M_t.lower_bound(__x); }
733
734#if __cplusplus > 201103L
735 template<typename _Kt>
736 auto
737 lower_bound(const _Kt& __x)
738 -> decltype(_M_t._M_lower_bound_tr(__x))
739 { return _M_t._M_lower_bound_tr(__x); }
740
741 template<typename _Kt>
742 auto
743 lower_bound(const _Kt& __x) const
744 -> decltype(_M_t._M_lower_bound_tr(__x))
745 { return _M_t._M_lower_bound_tr(__x); }
746#endif
747 //@}
748
749 //@{
750 /**
751 * @brief Finds the end of a subsequence matching given key.
752 * @param __x Key to be located.
753 * @return Iterator pointing to the first element
754 * greater than key, or end().
755 */
756 iterator
757 upper_bound(const key_type& __x)
758 { return _M_t.upper_bound(__x); }
759
760 const_iterator
761 upper_bound(const key_type& __x) const
762 { return _M_t.upper_bound(__x); }
763
764#if __cplusplus > 201103L
765 template<typename _Kt>
766 auto
767 upper_bound(const _Kt& __x)
768 -> decltype(_M_t._M_upper_bound_tr(__x))
769 { return _M_t._M_upper_bound_tr(__x); }
770
771 template<typename _Kt>
772 auto
773 upper_bound(const _Kt& __x) const
774 -> decltype(_M_t._M_upper_bound_tr(__x))
775 { return _M_t._M_upper_bound_tr(__x); }
776#endif
777 //@}
778
779 //@{
780 /**
781 * @brief Finds a subsequence matching given key.
782 * @param __x Key to be located.
783 * @return Pair of iterators that possibly points to the subsequence
784 * matching given key.
785 *
786 * This function is equivalent to
787 * @code
788 * std::make_pair(c.lower_bound(val),
789 * c.upper_bound(val))
790 * @endcode
791 * (but is faster than making the calls separately).
792 *
793 * This function probably only makes sense for multisets.
794 */
795 std::pair<iterator, iterator>
796 equal_range(const key_type& __x)
797 { return _M_t.equal_range(__x); }
798
799 std::pair<const_iterator, const_iterator>
800 equal_range(const key_type& __x) const
801 { return _M_t.equal_range(__x); }
802
803#if __cplusplus > 201103L
804 template<typename _Kt>
805 auto
806 equal_range(const _Kt& __x)
807 -> decltype(_M_t._M_equal_range_tr(__x))
808 { return _M_t._M_equal_range_tr(__x); }
809
810 template<typename _Kt>
811 auto
812 equal_range(const _Kt& __x) const
813 -> decltype(_M_t._M_equal_range_tr(__x))
814 { return _M_t._M_equal_range_tr(__x); }
815#endif
816 //@}
817
818 template<typename _K1, typename _C1, typename _A1>
819 friend bool
820 operator==(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
821
822 template<typename _K1, typename _C1, typename _A1>
823 friend bool
824 operator<(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
825 };
826
827
828 /**
829 * @brief Set equality comparison.
830 * @param __x A %set.
831 * @param __y A %set of the same type as @a x.
832 * @return True iff the size and elements of the sets are equal.
833 *
834 * This is an equivalence relation. It is linear in the size of the sets.
835 * Sets are considered equivalent if their sizes are equal, and if
836 * corresponding elements compare equal.
837 */
838 template<typename _Key, typename _Compare, typename _Alloc>
839 inline bool
840 operator==(const set<_Key, _Compare, _Alloc>& __x,
841 const set<_Key, _Compare, _Alloc>& __y)
842 { return __x._M_t == __y._M_t; }
843
844 /**
845 * @brief Set ordering relation.
846 * @param __x A %set.
847 * @param __y A %set of the same type as @a x.
848 * @return True iff @a __x is lexicographically less than @a __y.
849 *
850 * This is a total ordering relation. It is linear in the size of the
851 * sets. The elements must be comparable with @c <.
852 *
853 * See std::lexicographical_compare() for how the determination is made.
854 */
855 template<typename _Key, typename _Compare, typename _Alloc>
856 inline bool
857 operator<(const set<_Key, _Compare, _Alloc>& __x,
858 const set<_Key, _Compare, _Alloc>& __y)
859 { return __x._M_t < __y._M_t; }
860
861 /// Returns !(x == y).
862 template<typename _Key, typename _Compare, typename _Alloc>
863 inline bool
864 operator!=(const set<_Key, _Compare, _Alloc>& __x,
865 const set<_Key, _Compare, _Alloc>& __y)
866 { return !(__x == __y); }
867
868 /// Returns y < x.
869 template<typename _Key, typename _Compare, typename _Alloc>
870 inline bool
871 operator>(const set<_Key, _Compare, _Alloc>& __x,
872 const set<_Key, _Compare, _Alloc>& __y)
873 { return __y < __x; }
874
875 /// Returns !(y < x)
876 template<typename _Key, typename _Compare, typename _Alloc>
877 inline bool
878 operator<=(const set<_Key, _Compare, _Alloc>& __x,
879 const set<_Key, _Compare, _Alloc>& __y)
880 { return !(__y < __x); }
881
882 /// Returns !(x < y)
883 template<typename _Key, typename _Compare, typename _Alloc>
884 inline bool
885 operator>=(const set<_Key, _Compare, _Alloc>& __x,
886 const set<_Key, _Compare, _Alloc>& __y)
887 { return !(__x < __y); }
888
889 /// See std::set::swap().
890 template<typename _Key, typename _Compare, typename _Alloc>
891 inline void
892 swap(set<_Key, _Compare, _Alloc>& __x, set<_Key, _Compare, _Alloc>& __y)
893 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
894 { __x.swap(__y); }
895
896_GLIBCXX_END_NAMESPACE_CONTAINER
897} //namespace std
898#endif /* _STL_SET_H */
899