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.
146 * @brief Creates a %set with no elements.
147 * @param __comp Comparator to use.
148 * @param __a An allocator object.
151 set(const _Compare& __comp,
152 const allocator_type& __a = allocator_type())
153 : _M_t(__comp, _Key_alloc_type(__a)) { }
156 * @brief Builds a %set from a range.
157 * @param __first An input iterator.
158 * @param __last An input iterator.
160 * Create a %set consisting of copies of the elements from
161 * [__first,__last). This is linear in N if the range is
162 * already sorted, and NlogN otherwise (where N is
163 * distance(__first,__last)).
165 template<typename _InputIterator>
166 set(_InputIterator __first, _InputIterator __last)
168 { _M_t._M_insert_unique(__first, __last); }
171 * @brief Builds a %set from a range.
172 * @param __first An input iterator.
173 * @param __last An input iterator.
174 * @param __comp A comparison functor.
175 * @param __a An allocator object.
177 * Create a %set consisting of copies of the elements from
178 * [__first,__last). This is linear in N if the range is
179 * already sorted, and NlogN otherwise (where N is
180 * distance(__first,__last)).
182 template<typename _InputIterator>
183 set(_InputIterator __first, _InputIterator __last,
184 const _Compare& __comp,
185 const allocator_type& __a = allocator_type())
186 : _M_t(__comp, _Key_alloc_type(__a))
187 { _M_t._M_insert_unique(__first, __last); }
190 * @brief %Set copy constructor.
191 * @param __x A %set of identical element and allocator types.
193 * The newly-created %set uses a copy of the allocation object used
199 #if __cplusplus >= 201103L
201 * @brief %Set move constructor
202 * @param __x A %set of identical element and allocator types.
204 * The newly-created %set contains the exact contents of @a x.
205 * The contents of @a x are a valid, but unspecified %set.
208 noexcept(is_nothrow_copy_constructible<_Compare>::value)
209 : _M_t(std::move(__x._M_t)) { }
212 * @brief Builds a %set from an initializer_list.
213 * @param __l An initializer_list.
214 * @param __comp A comparison functor.
215 * @param __a An allocator object.
217 * Create a %set consisting of copies of the elements in the list.
218 * This is linear in N if the list is already sorted, and NlogN
219 * otherwise (where N is @a __l.size()).
221 set(initializer_list<value_type> __l,
222 const _Compare& __comp = _Compare(),
223 const allocator_type& __a = allocator_type())
224 : _M_t(__comp, _Key_alloc_type(__a))
225 { _M_t._M_insert_unique(__l.begin(), __l.end()); }
227 /// Allocator-extended default constructor.
229 set(const allocator_type& __a)
230 : _M_t(_Compare(), _Key_alloc_type(__a)) { }
232 /// Allocator-extended copy constructor.
233 set(const set& __x, const allocator_type& __a)
234 : _M_t(__x._M_t, _Key_alloc_type(__a)) { }
236 /// Allocator-extended move constructor.
237 set(set&& __x, const allocator_type& __a)
238 noexcept(is_nothrow_copy_constructible<_Compare>::value
239 && _Alloc_traits::_S_always_equal())
240 : _M_t(std::move(__x._M_t), _Key_alloc_type(__a)) { }
242 /// Allocator-extended initialier-list constructor.
243 set(initializer_list<value_type> __l, const allocator_type& __a)
244 : _M_t(_Compare(), _Key_alloc_type(__a))
245 { _M_t._M_insert_unique(__l.begin(), __l.end()); }
247 /// Allocator-extended range constructor.
248 template<typename _InputIterator>
249 set(_InputIterator __first, _InputIterator __last,
250 const allocator_type& __a)
251 : _M_t(_Compare(), _Key_alloc_type(__a))
252 { _M_t._M_insert_unique(__first, __last); }
256 * @brief %Set assignment operator.
257 * @param __x A %set of identical element and allocator types.
259 * All the elements of @a __x are copied, but unlike the copy
260 * constructor, the allocator object is not copied.
263 operator=(const set& __x)
269 #if __cplusplus >= 201103L
270 /// Move assignment operator.
272 operator=(set&&) = default;
275 * @brief %Set list assignment operator.
276 * @param __l An initializer_list.
278 * This function fills a %set with copies of the elements in the
279 * initializer list @a __l.
281 * Note that the assignment completely changes the %set and
282 * that the resulting %set's size is the same as the number
283 * of elements assigned. Old data may be lost.
286 operator=(initializer_list<value_type> __l)
288 _M_t._M_assign_unique(__l.begin(), __l.end());
295 /// Returns the comparison object with which the %set was constructed.
298 { return _M_t.key_comp(); }
299 /// Returns the comparison object with which the %set was constructed.
302 { return _M_t.key_comp(); }
303 /// Returns the allocator object with which the %set was constructed.
305 get_allocator() const _GLIBCXX_NOEXCEPT
306 { return allocator_type(_M_t.get_allocator()); }
309 * Returns a read-only (constant) iterator that points to the first
310 * element in the %set. Iteration is done in ascending order according
314 begin() const _GLIBCXX_NOEXCEPT
315 { return _M_t.begin(); }
318 * Returns a read-only (constant) iterator that points one past the last
319 * element in the %set. Iteration is done in ascending order according
323 end() const _GLIBCXX_NOEXCEPT
324 { return _M_t.end(); }
327 * Returns a read-only (constant) iterator that points to the last
328 * element in the %set. Iteration is done in descending order according
332 rbegin() const _GLIBCXX_NOEXCEPT
333 { return _M_t.rbegin(); }
336 * Returns a read-only (constant) reverse iterator that points to the
337 * last pair in the %set. Iteration is done in descending order
338 * according to the keys.
341 rend() const _GLIBCXX_NOEXCEPT
342 { return _M_t.rend(); }
344 #if __cplusplus >= 201103L
346 * Returns a read-only (constant) iterator that points to the first
347 * element in the %set. Iteration is done in ascending order according
351 cbegin() const noexcept
352 { return _M_t.begin(); }
355 * Returns a read-only (constant) iterator that points one past the last
356 * element in the %set. Iteration is done in ascending order according
360 cend() const noexcept
361 { return _M_t.end(); }
364 * Returns a read-only (constant) iterator that points to the last
365 * element in the %set. Iteration is done in descending order according
369 crbegin() const noexcept
370 { return _M_t.rbegin(); }
373 * Returns a read-only (constant) reverse iterator that points to the
374 * last pair in the %set. Iteration is done in descending order
375 * according to the keys.
378 crend() const noexcept
379 { return _M_t.rend(); }
382 /// Returns true if the %set is empty.
384 empty() const _GLIBCXX_NOEXCEPT
385 { return _M_t.empty(); }
387 /// Returns the size of the %set.
389 size() const _GLIBCXX_NOEXCEPT
390 { return _M_t.size(); }
392 /// Returns the maximum size of the %set.
394 max_size() const _GLIBCXX_NOEXCEPT
395 { return _M_t.max_size(); }
398 * @brief Swaps data with another %set.
399 * @param __x A %set of the same element and allocator types.
401 * This exchanges the elements between two sets in constant
402 * time. (It is only swapping a pointer, an integer, and an
403 * instance of the @c Compare type (which itself is often
404 * stateless and empty), so it should be quite fast.) Note
405 * that the global std::swap() function is specialized such
406 * that std::swap(s1,s2) will feed to this function.
410 #if __cplusplus >= 201103L
411 noexcept(_Alloc_traits::_S_nothrow_swap())
413 { _M_t.swap(__x._M_t); }
416 #if __cplusplus >= 201103L
418 * @brief Attempts to build and insert an element into the %set.
419 * @param __args Arguments used to generate an element.
420 * @return A pair, of which the first element is an iterator that points
421 * to the possibly inserted element, and the second is a bool
422 * that is true if the element was actually inserted.
424 * This function attempts to build and insert an element into the %set.
425 * A %set relies on unique keys and thus an element is only inserted if
426 * it is not already present in the %set.
428 * Insertion requires logarithmic time.
430 template<typename... _Args>
431 std::pair<iterator, bool>
432 emplace(_Args&&... __args)
433 { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
436 * @brief Attempts to insert an element into the %set.
437 * @param __pos An iterator that serves as a hint as to where the
438 * element should be inserted.
439 * @param __args Arguments used to generate the element to be
441 * @return An iterator that points to the element with key equivalent to
442 * the one generated from @a __args (may or may not be the
445 * This function is not concerned about whether the insertion took place,
446 * and thus does not return a boolean like the single-argument emplace()
447 * does. Note that the first parameter is only a hint and can
448 * potentially improve the performance of the insertion process. A bad
449 * hint would cause no gains in efficiency.
451 * For more on @a hinting, see:
452 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
454 * Insertion requires logarithmic time (if the hint is not taken).
456 template<typename... _Args>
458 emplace_hint(const_iterator __pos, _Args&&... __args)
460 return _M_t._M_emplace_hint_unique(__pos,
461 std::forward<_Args>(__args)...);
466 * @brief Attempts to insert an element into the %set.
467 * @param __x Element to be inserted.
468 * @return A pair, of which the first element is an iterator that points
469 * to the possibly inserted element, and the second is a bool
470 * that is true if the element was actually inserted.
472 * This function attempts to insert an element into the %set. A %set
473 * relies on unique keys and thus an element is only inserted if it is
474 * not already present in the %set.
476 * Insertion requires logarithmic time.
478 std::pair<iterator, bool>
479 insert(const value_type& __x)
481 std::pair<typename _Rep_type::iterator, bool> __p =
482 _M_t._M_insert_unique(__x);
483 return std::pair<iterator, bool>(__p.first, __p.second);
486 #if __cplusplus >= 201103L
487 std::pair<iterator, bool>
488 insert(value_type&& __x)
490 std::pair<typename _Rep_type::iterator, bool> __p =
491 _M_t._M_insert_unique(std::move(__x));
492 return std::pair<iterator, bool>(__p.first, __p.second);
497 * @brief Attempts to insert an element into the %set.
498 * @param __position An iterator that serves as a hint as to where the
499 * element should be inserted.
500 * @param __x Element to be inserted.
501 * @return An iterator that points to the element with key of
502 * @a __x (may or may not be the element passed in).
504 * This function is not concerned about whether the insertion took place,
505 * and thus does not return a boolean like the single-argument insert()
506 * does. Note that the first parameter is only a hint and can
507 * potentially improve the performance of the insertion process. A bad
508 * hint would cause no gains in efficiency.
510 * For more on @a hinting, see:
511 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
513 * Insertion requires logarithmic time (if the hint is not taken).
516 insert(const_iterator __position, const value_type& __x)
517 { return _M_t._M_insert_unique_(__position, __x); }
519 #if __cplusplus >= 201103L
521 insert(const_iterator __position, value_type&& __x)
522 { return _M_t._M_insert_unique_(__position, std::move(__x)); }
526 * @brief A template function that attempts to insert a range
528 * @param __first Iterator pointing to the start of the range to be
530 * @param __last Iterator pointing to the end of the range.
532 * Complexity similar to that of the range constructor.
534 template<typename _InputIterator>
536 insert(_InputIterator __first, _InputIterator __last)
537 { _M_t._M_insert_unique(__first, __last); }
539 #if __cplusplus >= 201103L
541 * @brief Attempts to insert a list of elements into the %set.
542 * @param __l A std::initializer_list<value_type> of elements
545 * Complexity similar to that of the range constructor.
548 insert(initializer_list<value_type> __l)
549 { this->insert(__l.begin(), __l.end()); }
552 #if __cplusplus >= 201103L
553 // _GLIBCXX_RESOLVE_LIB_DEFECTS
554 // DR 130. Associative erase should return an iterator.
556 * @brief Erases an element from a %set.
557 * @param __position An iterator pointing to the element to be erased.
558 * @return An iterator pointing to the element immediately following
559 * @a __position prior to the element being erased. If no such
560 * element exists, end() is returned.
562 * This function erases an element, pointed to by the given iterator,
563 * from a %set. Note that this function only erases the element, and
564 * that if the element is itself a pointer, the pointed-to memory is not
565 * touched in any way. Managing the pointer is the user's
568 _GLIBCXX_ABI_TAG_CXX11
570 erase(const_iterator __position)
571 { return _M_t.erase(__position); }
574 * @brief Erases an element from a %set.
575 * @param position An iterator pointing to the element to be erased.
577 * This function erases an element, pointed to by the given iterator,
578 * from a %set. Note that this function only erases the element, and
579 * that if the element is itself a pointer, the pointed-to memory is not
580 * touched in any way. Managing the pointer is the user's
584 erase(iterator __position)
585 { _M_t.erase(__position); }
589 * @brief Erases elements according to the provided key.
590 * @param __x Key of element to be erased.
591 * @return The number of elements erased.
593 * This function erases all the elements located by the given key from
595 * Note that this function only erases the element, and that if
596 * the element is itself a pointer, the pointed-to memory is not touched
597 * in any way. Managing the pointer is the user's responsibility.
600 erase(const key_type& __x)
601 { return _M_t.erase(__x); }
603 #if __cplusplus >= 201103L
604 // _GLIBCXX_RESOLVE_LIB_DEFECTS
605 // DR 130. Associative erase should return an iterator.
607 * @brief Erases a [__first,__last) range of elements from a %set.
608 * @param __first Iterator pointing to the start of the range to be
611 * @param __last Iterator pointing to the end of the range to
613 * @return The iterator @a __last.
615 * This function erases a sequence of elements from a %set.
616 * Note that this function only erases the element, and that if
617 * the element is itself a pointer, the pointed-to memory is not touched
618 * in any way. Managing the pointer is the user's responsibility.
620 _GLIBCXX_ABI_TAG_CXX11
622 erase(const_iterator __first, const_iterator __last)
623 { return _M_t.erase(__first, __last); }
626 * @brief Erases a [first,last) range of elements from a %set.
627 * @param __first Iterator pointing to the start of the range to be
629 * @param __last Iterator pointing to the end of the range to
632 * This function erases a sequence of elements from a %set.
633 * Note that this function only erases the element, and that if
634 * the element is itself a pointer, the pointed-to memory is not touched
635 * in any way. Managing the pointer is the user's responsibility.
638 erase(iterator __first, iterator __last)
639 { _M_t.erase(__first, __last); }
643 * Erases all elements in a %set. Note that this function only erases
644 * the elements, and that if the elements themselves are pointers, the
645 * pointed-to memory is not touched in any way. Managing the pointer is
646 * the user's responsibility.
649 clear() _GLIBCXX_NOEXCEPT
656 * @brief Finds the number of elements.
657 * @param __x Element to located.
658 * @return Number of elements with specified key.
660 * This function only makes sense for multisets; for set the result will
661 * either be 0 (not present) or 1 (present).
664 count(const key_type& __x) const
665 { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
667 #if __cplusplus > 201103L
668 template<typename _Kt>
670 count(const _Kt& __x) const
671 -> decltype(_M_t._M_count_tr(__x))
672 { return _M_t._M_find_tr(__x) == _M_t.end() ? 0 : 1; }
676 // _GLIBCXX_RESOLVE_LIB_DEFECTS
677 // 214. set::find() missing const overload
680 * @brief Tries to locate an element in a %set.
681 * @param __x Element to be located.
682 * @return Iterator pointing to sought-after element, or end() if not
685 * This function takes a key and tries to locate the element with which
686 * the key matches. If successful the function returns an iterator
687 * pointing to the sought after element. If unsuccessful it returns the
688 * past-the-end ( @c end() ) iterator.
691 find(const key_type& __x)
692 { return _M_t.find(__x); }
695 find(const key_type& __x) const
696 { return _M_t.find(__x); }
698 #if __cplusplus > 201103L
699 template<typename _Kt>
701 find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
702 { return _M_t._M_find_tr(__x); }
704 template<typename _Kt>
706 find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
707 { return _M_t._M_find_tr(__x); }
713 * @brief Finds the beginning of a subsequence matching given key.
714 * @param __x Key to be located.
715 * @return Iterator pointing to first element equal to or greater
716 * than key, or end().
718 * This function returns the first element of a subsequence of elements
719 * that matches the given key. If unsuccessful it returns an iterator
720 * pointing to the first element that has a greater value than given key
721 * or end() if no such element exists.
724 lower_bound(const key_type& __x)
725 { return _M_t.lower_bound(__x); }
728 lower_bound(const key_type& __x) const
729 { return _M_t.lower_bound(__x); }
731 #if __cplusplus > 201103L
732 template<typename _Kt>
734 lower_bound(const _Kt& __x)
735 -> decltype(_M_t._M_lower_bound_tr(__x))
736 { return _M_t._M_lower_bound_tr(__x); }
738 template<typename _Kt>
740 lower_bound(const _Kt& __x) const
741 -> decltype(_M_t._M_lower_bound_tr(__x))
742 { return _M_t._M_lower_bound_tr(__x); }
748 * @brief Finds the end of a subsequence matching given key.
749 * @param __x Key to be located.
750 * @return Iterator pointing to the first element
751 * greater than key, or end().
754 upper_bound(const key_type& __x)
755 { return _M_t.upper_bound(__x); }
758 upper_bound(const key_type& __x) const
759 { return _M_t.upper_bound(__x); }
761 #if __cplusplus > 201103L
762 template<typename _Kt>
764 upper_bound(const _Kt& __x)
765 -> decltype(_M_t._M_upper_bound_tr(__x))
766 { return _M_t._M_upper_bound_tr(__x); }
768 template<typename _Kt>
770 upper_bound(const _Kt& __x) const
771 -> decltype(_M_t._M_upper_bound_tr(__x))
772 { return _M_t._M_upper_bound_tr(__x); }
778 * @brief Finds a subsequence matching given key.
779 * @param __x Key to be located.
780 * @return Pair of iterators that possibly points to the subsequence
781 * matching given key.
783 * This function is equivalent to
785 * std::make_pair(c.lower_bound(val),
786 * c.upper_bound(val))
788 * (but is faster than making the calls separately).
790 * This function probably only makes sense for multisets.
792 std::pair<iterator, iterator>
793 equal_range(const key_type& __x)
794 { return _M_t.equal_range(__x); }
796 std::pair<const_iterator, const_iterator>
797 equal_range(const key_type& __x) const
798 { return _M_t.equal_range(__x); }
800 #if __cplusplus > 201103L
801 template<typename _Kt>
803 equal_range(const _Kt& __x)
804 -> decltype(_M_t._M_equal_range_tr(__x))
805 { return _M_t._M_equal_range_tr(__x); }
807 template<typename _Kt>
809 equal_range(const _Kt& __x) const
810 -> decltype(_M_t._M_equal_range_tr(__x))
811 { return _M_t._M_equal_range_tr(__x); }
815 template<typename _K1, typename _C1, typename _A1>
817 operator==(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
819 template<typename _K1, typename _C1, typename _A1>
821 operator<(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
826 * @brief Set equality comparison.
828 * @param __y A %set of the same type as @a x.
829 * @return True iff the size and elements of the sets are equal.
831 * This is an equivalence relation. It is linear in the size of the sets.
832 * Sets are considered equivalent if their sizes are equal, and if
833 * corresponding elements compare equal.
835 template<typename _Key, typename _Compare, typename _Alloc>
837 operator==(const set<_Key, _Compare, _Alloc>& __x,
838 const set<_Key, _Compare, _Alloc>& __y)
839 { return __x._M_t == __y._M_t; }
842 * @brief Set ordering relation.
844 * @param __y A %set of the same type as @a x.
845 * @return True iff @a __x is lexicographically less than @a __y.
847 * This is a total ordering relation. It is linear in the size of the
848 * sets. The elements must be comparable with @c <.
850 * See std::lexicographical_compare() for how the determination is made.
852 template<typename _Key, typename _Compare, typename _Alloc>
854 operator<(const set<_Key, _Compare, _Alloc>& __x,
855 const set<_Key, _Compare, _Alloc>& __y)
856 { return __x._M_t < __y._M_t; }
858 /// Returns !(x == y).
859 template<typename _Key, typename _Compare, typename _Alloc>
861 operator!=(const set<_Key, _Compare, _Alloc>& __x,
862 const set<_Key, _Compare, _Alloc>& __y)
863 { return !(__x == __y); }
866 template<typename _Key, typename _Compare, typename _Alloc>
868 operator>(const set<_Key, _Compare, _Alloc>& __x,
869 const set<_Key, _Compare, _Alloc>& __y)
870 { return __y < __x; }
873 template<typename _Key, typename _Compare, typename _Alloc>
875 operator<=(const set<_Key, _Compare, _Alloc>& __x,
876 const set<_Key, _Compare, _Alloc>& __y)
877 { return !(__y < __x); }
880 template<typename _Key, typename _Compare, typename _Alloc>
882 operator>=(const set<_Key, _Compare, _Alloc>& __x,
883 const set<_Key, _Compare, _Alloc>& __y)
884 { return !(__x < __y); }
886 /// See std::set::swap().
887 template<typename _Key, typename _Compare, typename _Alloc>
889 swap(set<_Key, _Compare, _Alloc>& __x, set<_Key, _Compare, _Alloc>& __y)
892 _GLIBCXX_END_NAMESPACE_CONTAINER
894 #endif /* _STL_SET_H */