1 // Set implementation -*- C++ -*-
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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}
59 #include <bits/concept_check.h>
60 #if __cplusplus >= 201103L
61 #include <initializer_list>
64 namespace std _GLIBCXX_VISIBILITY(default)
66 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
69 * @brief A standard container made up of unique keys, which can be
70 * retrieved in logarithmic time.
72 * @ingroup associative_containers
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>.
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).
82 * Sets support bidirectional iterators.
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).
88 template<typename _Key, typename _Compare = std::less<_Key>,
89 typename _Alloc = std::allocator<_Key> >
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)
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;
111 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
112 rebind<_Key>::other _Key_alloc_type;
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.
118 typedef __gnu_cxx::__alloc_traits<_Key_alloc_type> _Alloc_traits;
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;
138 // allocation/deallocation
140 * @brief Default constructor creates no elements.
143 #if __cplusplus >= 201103L
144 noexcept(is_nothrow_default_constructible<allocator_type>::value)
149 * @brief Creates a %set with no elements.
150 * @param __comp Comparator to use.
151 * @param __a An allocator object.
154 set(const _Compare& __comp,
155 const allocator_type& __a = allocator_type())
156 : _M_t(__comp, _Key_alloc_type(__a)) { }
159 * @brief Builds a %set from a range.
160 * @param __first An input iterator.
161 * @param __last An input iterator.
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)).
168 template<typename _InputIterator>
169 set(_InputIterator __first, _InputIterator __last)
171 { _M_t._M_insert_unique(__first, __last); }
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.
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)).
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); }
193 * @brief %Set copy constructor.
194 * @param __x A %set of identical element and allocator types.
196 * The newly-created %set uses a copy of the allocation object used
202 #if __cplusplus >= 201103L
204 * @brief %Set move constructor
205 * @param __x A %set of identical element and allocator types.
207 * The newly-created %set contains the exact contents of @a x.
208 * The contents of @a x are a valid, but unspecified %set.
211 noexcept(is_nothrow_copy_constructible<_Compare>::value)
212 : _M_t(std::move(__x._M_t)) { }
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.
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()).
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()); }
230 /// Allocator-extended default constructor.
232 set(const allocator_type& __a)
233 : _M_t(_Compare(), _Key_alloc_type(__a)) { }
235 /// Allocator-extended copy constructor.
236 set(const set& __x, const allocator_type& __a)
237 : _M_t(__x._M_t, _Key_alloc_type(__a)) { }
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)) { }
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()); }
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); }
259 * @brief %Set assignment operator.
260 * @param __x A %set of identical element and allocator types.
262 * All the elements of @a __x are copied, but unlike the copy
263 * constructor, the allocator object is not copied.
266 operator=(const set& __x)
272 #if __cplusplus >= 201103L
273 /// Move assignment operator.
275 operator=(set&&) = default;
278 * @brief %Set list assignment operator.
279 * @param __l An initializer_list.
281 * This function fills a %set with copies of the elements in the
282 * initializer list @a __l.
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.
289 operator=(initializer_list<value_type> __l)
291 _M_t._M_assign_unique(__l.begin(), __l.end());
298 /// Returns the comparison object with which the %set was constructed.
301 { return _M_t.key_comp(); }
302 /// Returns the comparison object with which the %set was constructed.
305 { return _M_t.key_comp(); }
306 /// Returns the allocator object with which the %set was constructed.
308 get_allocator() const _GLIBCXX_NOEXCEPT
309 { return allocator_type(_M_t.get_allocator()); }
312 * Returns a read-only (constant) iterator that points to the first
313 * element in the %set. Iteration is done in ascending order according
317 begin() const _GLIBCXX_NOEXCEPT
318 { return _M_t.begin(); }
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
326 end() const _GLIBCXX_NOEXCEPT
327 { return _M_t.end(); }
330 * Returns a read-only (constant) iterator that points to the last
331 * element in the %set. Iteration is done in descending order according
335 rbegin() const _GLIBCXX_NOEXCEPT
336 { return _M_t.rbegin(); }
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.
344 rend() const _GLIBCXX_NOEXCEPT
345 { return _M_t.rend(); }
347 #if __cplusplus >= 201103L
349 * Returns a read-only (constant) iterator that points to the first
350 * element in the %set. Iteration is done in ascending order according
354 cbegin() const noexcept
355 { return _M_t.begin(); }
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
363 cend() const noexcept
364 { return _M_t.end(); }
367 * Returns a read-only (constant) iterator that points to the last
368 * element in the %set. Iteration is done in descending order according
372 crbegin() const noexcept
373 { return _M_t.rbegin(); }
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.
381 crend() const noexcept
382 { return _M_t.rend(); }
385 /// Returns true if the %set is empty.
387 empty() const _GLIBCXX_NOEXCEPT
388 { return _M_t.empty(); }
390 /// Returns the size of the %set.
392 size() const _GLIBCXX_NOEXCEPT
393 { return _M_t.size(); }
395 /// Returns the maximum size of the %set.
397 max_size() const _GLIBCXX_NOEXCEPT
398 { return _M_t.max_size(); }
401 * @brief Swaps data with another %set.
402 * @param __x A %set of the same element and allocator types.
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.
413 #if __cplusplus >= 201103L
414 noexcept(_Alloc_traits::_S_nothrow_swap())
416 { _M_t.swap(__x._M_t); }
419 #if __cplusplus >= 201103L
421 * @brief Attempts to build and insert an element into the %set.
422 * @param __args Arguments used to generate an element.
423 * @return A pair, of which the first element is an iterator that points
424 * to the possibly inserted element, and the second is a bool
425 * that is true if the element was actually inserted.
427 * This function attempts to build and insert an element into the %set.
428 * A %set relies on unique keys and thus an element is only inserted if
429 * it is not already present in the %set.
431 * Insertion requires logarithmic time.
433 template<typename... _Args>
434 std::pair<iterator, bool>
435 emplace(_Args&&... __args)
436 { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
439 * @brief Attempts to insert an element into the %set.
440 * @param __pos An iterator that serves as a hint as to where the
441 * element should be inserted.
442 * @param __args Arguments used to generate the element to be
444 * @return An iterator that points to the element with key equivalent to
445 * the one generated from @a __args (may or may not be the
448 * This function is not concerned about whether the insertion took place,
449 * and thus does not return a boolean like the single-argument emplace()
450 * does. Note that the first parameter is only a hint and can
451 * potentially improve the performance of the insertion process. A bad
452 * hint would cause no gains in efficiency.
454 * For more on @a hinting, see:
455 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
457 * Insertion requires logarithmic time (if the hint is not taken).
459 template<typename... _Args>
461 emplace_hint(const_iterator __pos, _Args&&... __args)
463 return _M_t._M_emplace_hint_unique(__pos,
464 std::forward<_Args>(__args)...);
469 * @brief Attempts to insert an element into the %set.
470 * @param __x Element to be inserted.
471 * @return A pair, of which the first element is an iterator that points
472 * to the possibly inserted element, and the second is a bool
473 * that is true if the element was actually inserted.
475 * This function attempts to insert an element into the %set. A %set
476 * relies on unique keys and thus an element is only inserted if it is
477 * not already present in the %set.
479 * Insertion requires logarithmic time.
481 std::pair<iterator, bool>
482 insert(const value_type& __x)
484 std::pair<typename _Rep_type::iterator, bool> __p =
485 _M_t._M_insert_unique(__x);
486 return std::pair<iterator, bool>(__p.first, __p.second);
489 #if __cplusplus >= 201103L
490 std::pair<iterator, bool>
491 insert(value_type&& __x)
493 std::pair<typename _Rep_type::iterator, bool> __p =
494 _M_t._M_insert_unique(std::move(__x));
495 return std::pair<iterator, bool>(__p.first, __p.second);
500 * @brief Attempts to insert an element into the %set.
501 * @param __position An iterator that serves as a hint as to where the
502 * element should be inserted.
503 * @param __x Element to be inserted.
504 * @return An iterator that points to the element with key of
505 * @a __x (may or may not be the element passed in).
507 * This function is not concerned about whether the insertion took place,
508 * and thus does not return a boolean like the single-argument insert()
509 * does. Note that the first parameter is only a hint and can
510 * potentially improve the performance of the insertion process. A bad
511 * hint would cause no gains in efficiency.
513 * For more on @a hinting, see:
514 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
516 * Insertion requires logarithmic time (if the hint is not taken).
519 insert(const_iterator __position, const value_type& __x)
520 { return _M_t._M_insert_unique_(__position, __x); }
522 #if __cplusplus >= 201103L
524 insert(const_iterator __position, value_type&& __x)
525 { return _M_t._M_insert_unique_(__position, std::move(__x)); }
529 * @brief A template function that attempts to insert a range
531 * @param __first Iterator pointing to the start of the range to be
533 * @param __last Iterator pointing to the end of the range.
535 * Complexity similar to that of the range constructor.
537 template<typename _InputIterator>
539 insert(_InputIterator __first, _InputIterator __last)
540 { _M_t._M_insert_unique(__first, __last); }
542 #if __cplusplus >= 201103L
544 * @brief Attempts to insert a list of elements into the %set.
545 * @param __l A std::initializer_list<value_type> of elements
548 * Complexity similar to that of the range constructor.
551 insert(initializer_list<value_type> __l)
552 { this->insert(__l.begin(), __l.end()); }
555 #if __cplusplus >= 201103L
556 // _GLIBCXX_RESOLVE_LIB_DEFECTS
557 // DR 130. Associative erase should return an iterator.
559 * @brief Erases an element from a %set.
560 * @param __position An iterator pointing to the element to be erased.
561 * @return An iterator pointing to the element immediately following
562 * @a __position prior to the element being erased. If no such
563 * element exists, end() is returned.
565 * This function erases an element, pointed to by the given iterator,
566 * from a %set. Note that this function only erases the element, and
567 * that if the element is itself a pointer, the pointed-to memory is not
568 * touched in any way. Managing the pointer is the user's
571 _GLIBCXX_ABI_TAG_CXX11
573 erase(const_iterator __position)
574 { return _M_t.erase(__position); }
577 * @brief Erases an element from a %set.
578 * @param position An iterator pointing to the element to be erased.
580 * This function erases an element, pointed to by the given iterator,
581 * from a %set. Note that this function only erases the element, and
582 * that if the element is itself a pointer, the pointed-to memory is not
583 * touched in any way. Managing the pointer is the user's
587 erase(iterator __position)
588 { _M_t.erase(__position); }
592 * @brief Erases elements according to the provided key.
593 * @param __x Key of element to be erased.
594 * @return The number of elements erased.
596 * This function erases all the elements located by the given key from
598 * Note that this function only erases the element, and that if
599 * the element is itself a pointer, the pointed-to memory is not touched
600 * in any way. Managing the pointer is the user's responsibility.
603 erase(const key_type& __x)
604 { return _M_t.erase(__x); }
606 #if __cplusplus >= 201103L
607 // _GLIBCXX_RESOLVE_LIB_DEFECTS
608 // DR 130. Associative erase should return an iterator.
610 * @brief Erases a [__first,__last) range of elements from a %set.
611 * @param __first Iterator pointing to the start of the range to be
614 * @param __last Iterator pointing to the end of the range to
616 * @return The iterator @a __last.
618 * This function erases a sequence of elements from a %set.
619 * Note that this function only erases the element, and that if
620 * the element is itself a pointer, the pointed-to memory is not touched
621 * in any way. Managing the pointer is the user's responsibility.
623 _GLIBCXX_ABI_TAG_CXX11
625 erase(const_iterator __first, const_iterator __last)
626 { return _M_t.erase(__first, __last); }
629 * @brief Erases a [first,last) range of elements from a %set.
630 * @param __first Iterator pointing to the start of the range to be
632 * @param __last Iterator pointing to the end of the range to
635 * This function erases a sequence of elements from a %set.
636 * Note that this function only erases the element, and that if
637 * the element is itself a pointer, the pointed-to memory is not touched
638 * in any way. Managing the pointer is the user's responsibility.
641 erase(iterator __first, iterator __last)
642 { _M_t.erase(__first, __last); }
646 * Erases all elements in a %set. Note that this function only erases
647 * the elements, and that if the elements themselves are pointers, the
648 * pointed-to memory is not touched in any way. Managing the pointer is
649 * the user's responsibility.
652 clear() _GLIBCXX_NOEXCEPT
659 * @brief Finds the number of elements.
660 * @param __x Element to located.
661 * @return Number of elements with specified key.
663 * This function only makes sense for multisets; for set the result will
664 * either be 0 (not present) or 1 (present).
667 count(const key_type& __x) const
668 { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
670 #if __cplusplus > 201103L
671 template<typename _Kt>
673 count(const _Kt& __x) const
674 -> decltype(_M_t._M_count_tr(__x))
675 { return _M_t._M_find_tr(__x) == _M_t.end() ? 0 : 1; }
679 // _GLIBCXX_RESOLVE_LIB_DEFECTS
680 // 214. set::find() missing const overload
683 * @brief Tries to locate an element in a %set.
684 * @param __x Element to be located.
685 * @return Iterator pointing to sought-after element, or end() if not
688 * This function takes a key and tries to locate the element with which
689 * the key matches. If successful the function returns an iterator
690 * pointing to the sought after element. If unsuccessful it returns the
691 * past-the-end ( @c end() ) iterator.
694 find(const key_type& __x)
695 { return _M_t.find(__x); }
698 find(const key_type& __x) const
699 { return _M_t.find(__x); }
701 #if __cplusplus > 201103L
702 template<typename _Kt>
704 find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
705 { return _M_t._M_find_tr(__x); }
707 template<typename _Kt>
709 find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
710 { return _M_t._M_find_tr(__x); }
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().
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.
727 lower_bound(const key_type& __x)
728 { return _M_t.lower_bound(__x); }
731 lower_bound(const key_type& __x) const
732 { return _M_t.lower_bound(__x); }
734 #if __cplusplus > 201103L
735 template<typename _Kt>
737 lower_bound(const _Kt& __x)
738 -> decltype(_M_t._M_lower_bound_tr(__x))
739 { return _M_t._M_lower_bound_tr(__x); }
741 template<typename _Kt>
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); }
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().
757 upper_bound(const key_type& __x)
758 { return _M_t.upper_bound(__x); }
761 upper_bound(const key_type& __x) const
762 { return _M_t.upper_bound(__x); }
764 #if __cplusplus > 201103L
765 template<typename _Kt>
767 upper_bound(const _Kt& __x)
768 -> decltype(_M_t._M_upper_bound_tr(__x))
769 { return _M_t._M_upper_bound_tr(__x); }
771 template<typename _Kt>
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); }
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.
786 * This function is equivalent to
788 * std::make_pair(c.lower_bound(val),
789 * c.upper_bound(val))
791 * (but is faster than making the calls separately).
793 * This function probably only makes sense for multisets.
795 std::pair<iterator, iterator>
796 equal_range(const key_type& __x)
797 { return _M_t.equal_range(__x); }
799 std::pair<const_iterator, const_iterator>
800 equal_range(const key_type& __x) const
801 { return _M_t.equal_range(__x); }
803 #if __cplusplus > 201103L
804 template<typename _Kt>
806 equal_range(const _Kt& __x)
807 -> decltype(_M_t._M_equal_range_tr(__x))
808 { return _M_t._M_equal_range_tr(__x); }
810 template<typename _Kt>
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); }
818 template<typename _K1, typename _C1, typename _A1>
820 operator==(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
822 template<typename _K1, typename _C1, typename _A1>
824 operator<(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
829 * @brief Set equality comparison.
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.
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.
838 template<typename _Key, typename _Compare, typename _Alloc>
840 operator==(const set<_Key, _Compare, _Alloc>& __x,
841 const set<_Key, _Compare, _Alloc>& __y)
842 { return __x._M_t == __y._M_t; }
845 * @brief Set ordering relation.
847 * @param __y A %set of the same type as @a x.
848 * @return True iff @a __x is lexicographically less than @a __y.
850 * This is a total ordering relation. It is linear in the size of the
851 * sets. The elements must be comparable with @c <.
853 * See std::lexicographical_compare() for how the determination is made.
855 template<typename _Key, typename _Compare, typename _Alloc>
857 operator<(const set<_Key, _Compare, _Alloc>& __x,
858 const set<_Key, _Compare, _Alloc>& __y)
859 { return __x._M_t < __y._M_t; }
861 /// Returns !(x == y).
862 template<typename _Key, typename _Compare, typename _Alloc>
864 operator!=(const set<_Key, _Compare, _Alloc>& __x,
865 const set<_Key, _Compare, _Alloc>& __y)
866 { return !(__x == __y); }
869 template<typename _Key, typename _Compare, typename _Alloc>
871 operator>(const set<_Key, _Compare, _Alloc>& __x,
872 const set<_Key, _Compare, _Alloc>& __y)
873 { return __y < __x; }
876 template<typename _Key, typename _Compare, typename _Alloc>
878 operator<=(const set<_Key, _Compare, _Alloc>& __x,
879 const set<_Key, _Compare, _Alloc>& __y)
880 { return !(__y < __x); }
883 template<typename _Key, typename _Compare, typename _Alloc>
885 operator>=(const set<_Key, _Compare, _Alloc>& __x,
886 const set<_Key, _Compare, _Alloc>& __y)
887 { return !(__x < __y); }
889 /// See std::set::swap().
890 template<typename _Key, typename _Compare, typename _Alloc>
892 swap(set<_Key, _Compare, _Alloc>& __x, set<_Key, _Compare, _Alloc>& __y)
895 _GLIBCXX_END_NAMESPACE_CONTAINER
897 #endif /* _STL_SET_H */