libstdc++
stl_set.h
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00001 // Set implementation -*- C++ -*-
00002 
00003 // Copyright (C) 2001-2014 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /*
00026  *
00027  * Copyright (c) 1994
00028  * Hewlett-Packard Company
00029  *
00030  * Permission to use, copy, modify, distribute and sell this software
00031  * and its documentation for any purpose is hereby granted without fee,
00032  * provided that the above copyright notice appear in all copies and
00033  * that both that copyright notice and this permission notice appear
00034  * in supporting documentation.  Hewlett-Packard Company makes no
00035  * representations about the suitability of this software for any
00036  * purpose.  It is provided "as is" without express or implied warranty.
00037  *
00038  *
00039  * Copyright (c) 1996,1997
00040  * Silicon Graphics Computer Systems, Inc.
00041  *
00042  * Permission to use, copy, modify, distribute and sell this software
00043  * and its documentation for any purpose is hereby granted without fee,
00044  * provided that the above copyright notice appear in all copies and
00045  * that both that copyright notice and this permission notice appear
00046  * in supporting documentation.  Silicon Graphics makes no
00047  * representations about the suitability of this software for any
00048  * purpose.  It is provided "as is" without express or implied warranty.
00049  */
00050 
00051 /** @file bits/stl_set.h
00052  *  This is an internal header file, included by other library headers.
00053  *  Do not attempt to use it directly. @headername{set}
00054  */
00055 
00056 #ifndef _STL_SET_H
00057 #define _STL_SET_H 1
00058 
00059 #include <bits/concept_check.h>
00060 #if __cplusplus >= 201103L
00061 #include <initializer_list>
00062 #endif
00063 
00064 namespace std _GLIBCXX_VISIBILITY(default)
00065 {
00066 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
00067 
00068   /**
00069    *  @brief A standard container made up of unique keys, which can be
00070    *  retrieved in logarithmic time.
00071    *
00072    *  @ingroup associative_containers
00073    *
00074    *  @tparam _Key  Type of key objects.
00075    *  @tparam _Compare  Comparison function object type, defaults to less<_Key>.
00076    *  @tparam _Alloc  Allocator type, defaults to allocator<_Key>.
00077    *
00078    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
00079    *  <a href="tables.html#66">reversible container</a>, and an
00080    *  <a href="tables.html#69">associative container</a> (using unique keys).
00081    *
00082    *  Sets support bidirectional iterators.
00083    *
00084    *  The private tree data is declared exactly the same way for set and
00085    *  multiset; the distinction is made entirely in how the tree functions are
00086    *  called (*_unique versus *_equal, same as the standard).
00087   */
00088   template<typename _Key, typename _Compare = std::less<_Key>,
00089        typename _Alloc = std::allocator<_Key> >
00090     class set
00091     {
00092       // concept requirements
00093       typedef typename _Alloc::value_type                   _Alloc_value_type;
00094       __glibcxx_class_requires(_Key, _SGIAssignableConcept)
00095       __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
00096                 _BinaryFunctionConcept)
00097       __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept)
00098 
00099     public:
00100       // typedefs:
00101       //@{
00102       /// Public typedefs.
00103       typedef _Key     key_type;
00104       typedef _Key     value_type;
00105       typedef _Compare key_compare;
00106       typedef _Compare value_compare;
00107       typedef _Alloc   allocator_type;
00108       //@}
00109 
00110     private:
00111       typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
00112     rebind<_Key>::other _Key_alloc_type;
00113 
00114       typedef _Rb_tree<key_type, value_type, _Identity<value_type>,
00115                key_compare, _Key_alloc_type> _Rep_type;
00116       _Rep_type _M_t;  // Red-black tree representing set.
00117 
00118       typedef __gnu_cxx::__alloc_traits<_Key_alloc_type> _Alloc_traits;
00119 
00120     public:
00121       //@{
00122       ///  Iterator-related typedefs.
00123       typedef typename _Alloc_traits::pointer           pointer;
00124       typedef typename _Alloc_traits::const_pointer     const_pointer;
00125       typedef typename _Alloc_traits::reference         reference;
00126       typedef typename _Alloc_traits::const_reference       const_reference;
00127       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00128       // DR 103. set::iterator is required to be modifiable,
00129       // but this allows modification of keys.
00130       typedef typename _Rep_type::const_iterator            iterator;
00131       typedef typename _Rep_type::const_iterator            const_iterator;
00132       typedef typename _Rep_type::const_reverse_iterator    reverse_iterator;
00133       typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
00134       typedef typename _Rep_type::size_type                 size_type;
00135       typedef typename _Rep_type::difference_type           difference_type;
00136       //@}
00137 
00138       // allocation/deallocation
00139       /**
00140        *  @brief  Default constructor creates no elements.
00141        */
00142       set()
00143       : _M_t() { }
00144 
00145       /**
00146        *  @brief  Creates a %set with no elements.
00147        *  @param  __comp  Comparator to use.
00148        *  @param  __a  An allocator object.
00149        */
00150       explicit
00151       set(const _Compare& __comp,
00152       const allocator_type& __a = allocator_type())
00153       : _M_t(__comp, _Key_alloc_type(__a)) { }
00154 
00155       /**
00156        *  @brief  Builds a %set from a range.
00157        *  @param  __first  An input iterator.
00158        *  @param  __last  An input iterator.
00159        *
00160        *  Create a %set consisting of copies of the elements from
00161        *  [__first,__last).  This is linear in N if the range is
00162        *  already sorted, and NlogN otherwise (where N is
00163        *  distance(__first,__last)).
00164        */
00165       template<typename _InputIterator>
00166     set(_InputIterator __first, _InputIterator __last)
00167     : _M_t()
00168     { _M_t._M_insert_unique(__first, __last); }
00169 
00170       /**
00171        *  @brief  Builds a %set from a range.
00172        *  @param  __first  An input iterator.
00173        *  @param  __last  An input iterator.
00174        *  @param  __comp  A comparison functor.
00175        *  @param  __a  An allocator object.
00176        *
00177        *  Create a %set consisting of copies of the elements from
00178        *  [__first,__last).  This is linear in N if the range is
00179        *  already sorted, and NlogN otherwise (where N is
00180        *  distance(__first,__last)).
00181        */
00182       template<typename _InputIterator>
00183     set(_InputIterator __first, _InputIterator __last,
00184         const _Compare& __comp,
00185         const allocator_type& __a = allocator_type())
00186     : _M_t(__comp, _Key_alloc_type(__a))
00187         { _M_t._M_insert_unique(__first, __last); }
00188 
00189       /**
00190        *  @brief  %Set copy constructor.
00191        *  @param  __x  A %set of identical element and allocator types.
00192        *
00193        *  The newly-created %set uses a copy of the allocation object used
00194        *  by @a __x.
00195        */
00196       set(const set& __x)
00197       : _M_t(__x._M_t) { }
00198 
00199 #if __cplusplus >= 201103L
00200      /**
00201        *  @brief %Set move constructor
00202        *  @param __x  A %set of identical element and allocator types.
00203        *
00204        *  The newly-created %set contains the exact contents of @a x.
00205        *  The contents of @a x are a valid, but unspecified %set.
00206        */
00207       set(set&& __x)
00208       noexcept(is_nothrow_copy_constructible<_Compare>::value)
00209       : _M_t(std::move(__x._M_t)) { }
00210 
00211       /**
00212        *  @brief  Builds a %set from an initializer_list.
00213        *  @param  __l  An initializer_list.
00214        *  @param  __comp  A comparison functor.
00215        *  @param  __a  An allocator object.
00216        *
00217        *  Create a %set consisting of copies of the elements in the list.
00218        *  This is linear in N if the list is already sorted, and NlogN
00219        *  otherwise (where N is @a __l.size()).
00220        */
00221       set(initializer_list<value_type> __l,
00222       const _Compare& __comp = _Compare(),
00223       const allocator_type& __a = allocator_type())
00224       : _M_t(__comp, _Key_alloc_type(__a))
00225       { _M_t._M_insert_unique(__l.begin(), __l.end()); }
00226 
00227       /// Allocator-extended default constructor.
00228       explicit
00229       set(const allocator_type& __a)
00230       : _M_t(_Compare(), _Key_alloc_type(__a)) { }
00231 
00232       /// Allocator-extended copy constructor.
00233       set(const set& __x, const allocator_type& __a)
00234       : _M_t(__x._M_t, _Key_alloc_type(__a)) { }
00235 
00236       /// Allocator-extended move constructor.
00237       set(set&& __x, const allocator_type& __a)
00238       noexcept(is_nothrow_copy_constructible<_Compare>::value
00239            && _Alloc_traits::_S_always_equal())
00240       : _M_t(std::move(__x._M_t), _Key_alloc_type(__a)) { }
00241 
00242       /// Allocator-extended initialier-list constructor.
00243       set(initializer_list<value_type> __l, const allocator_type& __a)
00244       : _M_t(_Compare(), _Key_alloc_type(__a))
00245       { _M_t._M_insert_unique(__l.begin(), __l.end()); }
00246 
00247       /// Allocator-extended range constructor.
00248       template<typename _InputIterator>
00249         set(_InputIterator __first, _InputIterator __last,
00250         const allocator_type& __a)
00251     : _M_t(_Compare(), _Key_alloc_type(__a))
00252         { _M_t._M_insert_unique(__first, __last); }
00253 #endif
00254 
00255       /**
00256        *  @brief  %Set assignment operator.
00257        *  @param  __x  A %set of identical element and allocator types.
00258        *
00259        *  All the elements of @a __x are copied, but unlike the copy
00260        *  constructor, the allocator object is not copied.
00261        */
00262       set&
00263       operator=(const set& __x)
00264       {
00265     _M_t = __x._M_t;
00266     return *this;
00267       }
00268 
00269 #if __cplusplus >= 201103L
00270       /**
00271        *  @brief %Set move assignment operator.
00272        *  @param __x  A %set of identical element and allocator types.
00273        *
00274        *  The contents of @a __x are moved into this %set (without copying
00275        *  if the allocators compare equal or get moved on assignment).
00276        *  Afterwards @a __x is in a valid, but unspecified state.
00277        */
00278       set&
00279       operator=(set&& __x) noexcept(_Alloc_traits::_S_nothrow_move())
00280       {
00281     if (!_M_t._M_move_assign(__x._M_t))
00282       {
00283         // The rvalue's allocator cannot be moved and is not equal,
00284         // so we need to individually move each element.
00285         clear();
00286         insert(std::__make_move_if_noexcept_iterator(__x._M_t.begin()),
00287            std::__make_move_if_noexcept_iterator(__x._M_t.end()));
00288         __x.clear();
00289       }
00290         return *this;
00291       }
00292 
00293       /**
00294        *  @brief  %Set list assignment operator.
00295        *  @param  __l  An initializer_list.
00296        *
00297        *  This function fills a %set with copies of the elements in the
00298        *  initializer list @a __l.
00299        *
00300        *  Note that the assignment completely changes the %set and
00301        *  that the resulting %set's size is the same as the number
00302        *  of elements assigned.  Old data may be lost.
00303        */
00304       set&
00305       operator=(initializer_list<value_type> __l)
00306       {
00307     this->clear();
00308     this->insert(__l.begin(), __l.end());
00309     return *this;
00310       }
00311 #endif
00312 
00313       // accessors:
00314 
00315       ///  Returns the comparison object with which the %set was constructed.
00316       key_compare
00317       key_comp() const
00318       { return _M_t.key_comp(); }
00319       ///  Returns the comparison object with which the %set was constructed.
00320       value_compare
00321       value_comp() const
00322       { return _M_t.key_comp(); }
00323       ///  Returns the allocator object with which the %set was constructed.
00324       allocator_type
00325       get_allocator() const _GLIBCXX_NOEXCEPT
00326       { return allocator_type(_M_t.get_allocator()); }
00327 
00328       /**
00329        *  Returns a read-only (constant) iterator that points to the first
00330        *  element in the %set.  Iteration is done in ascending order according
00331        *  to the keys.
00332        */
00333       iterator
00334       begin() const _GLIBCXX_NOEXCEPT
00335       { return _M_t.begin(); }
00336 
00337       /**
00338        *  Returns a read-only (constant) iterator that points one past the last
00339        *  element in the %set.  Iteration is done in ascending order according
00340        *  to the keys.
00341        */
00342       iterator
00343       end() const _GLIBCXX_NOEXCEPT
00344       { return _M_t.end(); }
00345 
00346       /**
00347        *  Returns a read-only (constant) iterator that points to the last
00348        *  element in the %set.  Iteration is done in descending order according
00349        *  to the keys.
00350        */
00351       reverse_iterator
00352       rbegin() const _GLIBCXX_NOEXCEPT
00353       { return _M_t.rbegin(); }
00354 
00355       /**
00356        *  Returns a read-only (constant) reverse iterator that points to the
00357        *  last pair in the %set.  Iteration is done in descending order
00358        *  according to the keys.
00359        */
00360       reverse_iterator
00361       rend() const _GLIBCXX_NOEXCEPT
00362       { return _M_t.rend(); }
00363 
00364 #if __cplusplus >= 201103L
00365       /**
00366        *  Returns a read-only (constant) iterator that points to the first
00367        *  element in the %set.  Iteration is done in ascending order according
00368        *  to the keys.
00369        */
00370       iterator
00371       cbegin() const noexcept
00372       { return _M_t.begin(); }
00373 
00374       /**
00375        *  Returns a read-only (constant) iterator that points one past the last
00376        *  element in the %set.  Iteration is done in ascending order according
00377        *  to the keys.
00378        */
00379       iterator
00380       cend() const noexcept
00381       { return _M_t.end(); }
00382 
00383       /**
00384        *  Returns a read-only (constant) iterator that points to the last
00385        *  element in the %set.  Iteration is done in descending order according
00386        *  to the keys.
00387        */
00388       reverse_iterator
00389       crbegin() const noexcept
00390       { return _M_t.rbegin(); }
00391 
00392       /**
00393        *  Returns a read-only (constant) reverse iterator that points to the
00394        *  last pair in the %set.  Iteration is done in descending order
00395        *  according to the keys.
00396        */
00397       reverse_iterator
00398       crend() const noexcept
00399       { return _M_t.rend(); }
00400 #endif
00401 
00402       ///  Returns true if the %set is empty.
00403       bool
00404       empty() const _GLIBCXX_NOEXCEPT
00405       { return _M_t.empty(); }
00406 
00407       ///  Returns the size of the %set.
00408       size_type
00409       size() const _GLIBCXX_NOEXCEPT
00410       { return _M_t.size(); }
00411 
00412       ///  Returns the maximum size of the %set.
00413       size_type
00414       max_size() const _GLIBCXX_NOEXCEPT
00415       { return _M_t.max_size(); }
00416 
00417       /**
00418        *  @brief  Swaps data with another %set.
00419        *  @param  __x  A %set of the same element and allocator types.
00420        *
00421        *  This exchanges the elements between two sets in constant
00422        *  time.  (It is only swapping a pointer, an integer, and an
00423        *  instance of the @c Compare type (which itself is often
00424        *  stateless and empty), so it should be quite fast.)  Note
00425        *  that the global std::swap() function is specialized such
00426        *  that std::swap(s1,s2) will feed to this function.
00427        */
00428       void
00429       swap(set& __x)
00430 #if __cplusplus >= 201103L
00431       noexcept(_Alloc_traits::_S_nothrow_swap())
00432 #endif
00433       { _M_t.swap(__x._M_t); }
00434 
00435       // insert/erase
00436 #if __cplusplus >= 201103L
00437       /**
00438        *  @brief Attempts to build and insert an element into the %set.
00439        *  @param __args  Arguments used to generate an element.
00440        *  @return  A pair, of which the first element is an iterator that points
00441        *           to the possibly inserted element, and the second is a bool
00442        *           that is true if the element was actually inserted.
00443        *
00444        *  This function attempts to build and insert an element into the %set.
00445        *  A %set relies on unique keys and thus an element is only inserted if
00446        *  it is not already present in the %set.
00447        *
00448        *  Insertion requires logarithmic time.
00449        */
00450       template<typename... _Args>
00451     std::pair<iterator, bool>
00452     emplace(_Args&&... __args)
00453     { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
00454 
00455       /**
00456        *  @brief Attempts to insert an element into the %set.
00457        *  @param  __pos  An iterator that serves as a hint as to where the
00458        *                element should be inserted.
00459        *  @param  __args  Arguments used to generate the element to be
00460        *                 inserted.
00461        *  @return An iterator that points to the element with key equivalent to
00462        *          the one generated from @a __args (may or may not be the
00463        *          element itself).
00464        *
00465        *  This function is not concerned about whether the insertion took place,
00466        *  and thus does not return a boolean like the single-argument emplace()
00467        *  does.  Note that the first parameter is only a hint and can
00468        *  potentially improve the performance of the insertion process.  A bad
00469        *  hint would cause no gains in efficiency.
00470        *
00471        *  For more on @a hinting, see:
00472        *  http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
00473        *
00474        *  Insertion requires logarithmic time (if the hint is not taken).
00475        */
00476       template<typename... _Args>
00477     iterator
00478     emplace_hint(const_iterator __pos, _Args&&... __args)
00479     {
00480       return _M_t._M_emplace_hint_unique(__pos,
00481                          std::forward<_Args>(__args)...);
00482     }
00483 #endif
00484 
00485       /**
00486        *  @brief Attempts to insert an element into the %set.
00487        *  @param  __x  Element to be inserted.
00488        *  @return  A pair, of which the first element is an iterator that points
00489        *           to the possibly inserted element, and the second is a bool
00490        *           that is true if the element was actually inserted.
00491        *
00492        *  This function attempts to insert an element into the %set.  A %set
00493        *  relies on unique keys and thus an element is only inserted if it is
00494        *  not already present in the %set.
00495        *
00496        *  Insertion requires logarithmic time.
00497        */
00498       std::pair<iterator, bool>
00499       insert(const value_type& __x)
00500       {
00501     std::pair<typename _Rep_type::iterator, bool> __p =
00502       _M_t._M_insert_unique(__x);
00503     return std::pair<iterator, bool>(__p.first, __p.second);
00504       }
00505 
00506 #if __cplusplus >= 201103L
00507       std::pair<iterator, bool>
00508       insert(value_type&& __x)
00509       {
00510     std::pair<typename _Rep_type::iterator, bool> __p =
00511       _M_t._M_insert_unique(std::move(__x));
00512     return std::pair<iterator, bool>(__p.first, __p.second);
00513       }
00514 #endif
00515 
00516       /**
00517        *  @brief Attempts to insert an element into the %set.
00518        *  @param  __position  An iterator that serves as a hint as to where the
00519        *                    element should be inserted.
00520        *  @param  __x  Element to be inserted.
00521        *  @return An iterator that points to the element with key of
00522        *           @a __x (may or may not be the element passed in).
00523        *
00524        *  This function is not concerned about whether the insertion took place,
00525        *  and thus does not return a boolean like the single-argument insert()
00526        *  does.  Note that the first parameter is only a hint and can
00527        *  potentially improve the performance of the insertion process.  A bad
00528        *  hint would cause no gains in efficiency.
00529        *
00530        *  For more on @a hinting, see:
00531        *  http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
00532        *
00533        *  Insertion requires logarithmic time (if the hint is not taken).
00534        */
00535       iterator
00536       insert(const_iterator __position, const value_type& __x)
00537       { return _M_t._M_insert_unique_(__position, __x); }
00538 
00539 #if __cplusplus >= 201103L
00540       iterator
00541       insert(const_iterator __position, value_type&& __x)
00542       { return _M_t._M_insert_unique_(__position, std::move(__x)); }
00543 #endif
00544 
00545       /**
00546        *  @brief A template function that attempts to insert a range
00547        *  of elements.
00548        *  @param  __first  Iterator pointing to the start of the range to be
00549        *                   inserted.
00550        *  @param  __last  Iterator pointing to the end of the range.
00551        *
00552        *  Complexity similar to that of the range constructor.
00553        */
00554       template<typename _InputIterator>
00555     void
00556     insert(_InputIterator __first, _InputIterator __last)
00557     { _M_t._M_insert_unique(__first, __last); }
00558 
00559 #if __cplusplus >= 201103L
00560       /**
00561        *  @brief Attempts to insert a list of elements into the %set.
00562        *  @param  __l  A std::initializer_list<value_type> of elements
00563        *               to be inserted.
00564        *
00565        *  Complexity similar to that of the range constructor.
00566        */
00567       void
00568       insert(initializer_list<value_type> __l)
00569       { this->insert(__l.begin(), __l.end()); }
00570 #endif
00571 
00572 #if __cplusplus >= 201103L
00573       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00574       // DR 130. Associative erase should return an iterator.
00575       /**
00576        *  @brief Erases an element from a %set.
00577        *  @param  __position  An iterator pointing to the element to be erased.
00578        *  @return An iterator pointing to the element immediately following
00579        *          @a __position prior to the element being erased. If no such
00580        *          element exists, end() is returned.
00581        *
00582        *  This function erases an element, pointed to by the given iterator,
00583        *  from a %set.  Note that this function only erases the element, and
00584        *  that if the element is itself a pointer, the pointed-to memory is not
00585        *  touched in any way.  Managing the pointer is the user's
00586        *  responsibility.
00587        */
00588       _GLIBCXX_ABI_TAG_CXX11
00589       iterator
00590       erase(const_iterator __position)
00591       { return _M_t.erase(__position); }
00592 #else
00593       /**
00594        *  @brief Erases an element from a %set.
00595        *  @param  position  An iterator pointing to the element to be erased.
00596        *
00597        *  This function erases an element, pointed to by the given iterator,
00598        *  from a %set.  Note that this function only erases the element, and
00599        *  that if the element is itself a pointer, the pointed-to memory is not
00600        *  touched in any way.  Managing the pointer is the user's
00601        *  responsibility.
00602        */
00603       void
00604       erase(iterator __position)
00605       { _M_t.erase(__position); }
00606 #endif
00607 
00608       /**
00609        *  @brief Erases elements according to the provided key.
00610        *  @param  __x  Key of element to be erased.
00611        *  @return  The number of elements erased.
00612        *
00613        *  This function erases all the elements located by the given key from
00614        *  a %set.
00615        *  Note that this function only erases the element, and that if
00616        *  the element is itself a pointer, the pointed-to memory is not touched
00617        *  in any way.  Managing the pointer is the user's responsibility.
00618        */
00619       size_type
00620       erase(const key_type& __x)
00621       { return _M_t.erase(__x); }
00622 
00623 #if __cplusplus >= 201103L
00624       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00625       // DR 130. Associative erase should return an iterator.
00626       /**
00627        *  @brief Erases a [__first,__last) range of elements from a %set.
00628        *  @param  __first  Iterator pointing to the start of the range to be
00629        *                 erased.
00630 
00631        *  @param __last Iterator pointing to the end of the range to
00632        *  be erased.
00633        *  @return The iterator @a __last.
00634        *
00635        *  This function erases a sequence of elements from a %set.
00636        *  Note that this function only erases the element, and that if
00637        *  the element is itself a pointer, the pointed-to memory is not touched
00638        *  in any way.  Managing the pointer is the user's responsibility.
00639        */
00640       _GLIBCXX_ABI_TAG_CXX11
00641       iterator
00642       erase(const_iterator __first, const_iterator __last)
00643       { return _M_t.erase(__first, __last); }
00644 #else
00645       /**
00646        *  @brief Erases a [first,last) range of elements from a %set.
00647        *  @param  __first  Iterator pointing to the start of the range to be
00648        *                 erased.
00649        *  @param __last Iterator pointing to the end of the range to
00650        *  be erased.
00651        *
00652        *  This function erases a sequence of elements from a %set.
00653        *  Note that this function only erases the element, and that if
00654        *  the element is itself a pointer, the pointed-to memory is not touched
00655        *  in any way.  Managing the pointer is the user's responsibility.
00656        */
00657       void
00658       erase(iterator __first, iterator __last)
00659       { _M_t.erase(__first, __last); }
00660 #endif
00661 
00662       /**
00663        *  Erases all elements in a %set.  Note that this function only erases
00664        *  the elements, and that if the elements themselves are pointers, the
00665        *  pointed-to memory is not touched in any way.  Managing the pointer is
00666        *  the user's responsibility.
00667        */
00668       void
00669       clear() _GLIBCXX_NOEXCEPT
00670       { _M_t.clear(); }
00671 
00672       // set operations:
00673 
00674       /**
00675        *  @brief  Finds the number of elements.
00676        *  @param  __x  Element to located.
00677        *  @return  Number of elements with specified key.
00678        *
00679        *  This function only makes sense for multisets; for set the result will
00680        *  either be 0 (not present) or 1 (present).
00681        */
00682       size_type
00683       count(const key_type& __x) const
00684       { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
00685 
00686       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00687       // 214.  set::find() missing const overload
00688       //@{
00689       /**
00690        *  @brief Tries to locate an element in a %set.
00691        *  @param  __x  Element to be located.
00692        *  @return  Iterator pointing to sought-after element, or end() if not
00693        *           found.
00694        *
00695        *  This function takes a key and tries to locate the element with which
00696        *  the key matches.  If successful the function returns an iterator
00697        *  pointing to the sought after element.  If unsuccessful it returns the
00698        *  past-the-end ( @c end() ) iterator.
00699        */
00700       iterator
00701       find(const key_type& __x)
00702       { return _M_t.find(__x); }
00703 
00704       const_iterator
00705       find(const key_type& __x) const
00706       { return _M_t.find(__x); }
00707       //@}
00708 
00709       //@{
00710       /**
00711        *  @brief Finds the beginning of a subsequence matching given key.
00712        *  @param  __x  Key to be located.
00713        *  @return  Iterator pointing to first element equal to or greater
00714        *           than key, or end().
00715        *
00716        *  This function returns the first element of a subsequence of elements
00717        *  that matches the given key.  If unsuccessful it returns an iterator
00718        *  pointing to the first element that has a greater value than given key
00719        *  or end() if no such element exists.
00720        */
00721       iterator
00722       lower_bound(const key_type& __x)
00723       { return _M_t.lower_bound(__x); }
00724 
00725       const_iterator
00726       lower_bound(const key_type& __x) const
00727       { return _M_t.lower_bound(__x); }
00728       //@}
00729 
00730       //@{
00731       /**
00732        *  @brief Finds the end of a subsequence matching given key.
00733        *  @param  __x  Key to be located.
00734        *  @return Iterator pointing to the first element
00735        *          greater than key, or end().
00736        */
00737       iterator
00738       upper_bound(const key_type& __x)
00739       { return _M_t.upper_bound(__x); }
00740 
00741       const_iterator
00742       upper_bound(const key_type& __x) const
00743       { return _M_t.upper_bound(__x); }
00744       //@}
00745 
00746       //@{
00747       /**
00748        *  @brief Finds a subsequence matching given key.
00749        *  @param  __x  Key to be located.
00750        *  @return  Pair of iterators that possibly points to the subsequence
00751        *           matching given key.
00752        *
00753        *  This function is equivalent to
00754        *  @code
00755        *    std::make_pair(c.lower_bound(val),
00756        *                   c.upper_bound(val))
00757        *  @endcode
00758        *  (but is faster than making the calls separately).
00759        *
00760        *  This function probably only makes sense for multisets.
00761        */
00762       std::pair<iterator, iterator>
00763       equal_range(const key_type& __x)
00764       { return _M_t.equal_range(__x); }
00765 
00766       std::pair<const_iterator, const_iterator>
00767       equal_range(const key_type& __x) const
00768       { return _M_t.equal_range(__x); }
00769       //@}
00770 
00771       template<typename _K1, typename _C1, typename _A1>
00772     friend bool
00773     operator==(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
00774 
00775       template<typename _K1, typename _C1, typename _A1>
00776     friend bool
00777     operator<(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
00778     };
00779 
00780 
00781   /**
00782    *  @brief  Set equality comparison.
00783    *  @param  __x  A %set.
00784    *  @param  __y  A %set of the same type as @a x.
00785    *  @return  True iff the size and elements of the sets are equal.
00786    *
00787    *  This is an equivalence relation.  It is linear in the size of the sets.
00788    *  Sets are considered equivalent if their sizes are equal, and if
00789    *  corresponding elements compare equal.
00790   */
00791   template<typename _Key, typename _Compare, typename _Alloc>
00792     inline bool
00793     operator==(const set<_Key, _Compare, _Alloc>& __x,
00794            const set<_Key, _Compare, _Alloc>& __y)
00795     { return __x._M_t == __y._M_t; }
00796 
00797   /**
00798    *  @brief  Set ordering relation.
00799    *  @param  __x  A %set.
00800    *  @param  __y  A %set of the same type as @a x.
00801    *  @return  True iff @a __x is lexicographically less than @a __y.
00802    *
00803    *  This is a total ordering relation.  It is linear in the size of the
00804    *  sets.  The elements must be comparable with @c <.
00805    *
00806    *  See std::lexicographical_compare() for how the determination is made.
00807   */
00808   template<typename _Key, typename _Compare, typename _Alloc>
00809     inline bool
00810     operator<(const set<_Key, _Compare, _Alloc>& __x,
00811           const set<_Key, _Compare, _Alloc>& __y)
00812     { return __x._M_t < __y._M_t; }
00813 
00814   ///  Returns !(x == y).
00815   template<typename _Key, typename _Compare, typename _Alloc>
00816     inline bool
00817     operator!=(const set<_Key, _Compare, _Alloc>& __x,
00818            const set<_Key, _Compare, _Alloc>& __y)
00819     { return !(__x == __y); }
00820 
00821   ///  Returns y < x.
00822   template<typename _Key, typename _Compare, typename _Alloc>
00823     inline bool
00824     operator>(const set<_Key, _Compare, _Alloc>& __x,
00825           const set<_Key, _Compare, _Alloc>& __y)
00826     { return __y < __x; }
00827 
00828   ///  Returns !(y < x)
00829   template<typename _Key, typename _Compare, typename _Alloc>
00830     inline bool
00831     operator<=(const set<_Key, _Compare, _Alloc>& __x,
00832            const set<_Key, _Compare, _Alloc>& __y)
00833     { return !(__y < __x); }
00834 
00835   ///  Returns !(x < y)
00836   template<typename _Key, typename _Compare, typename _Alloc>
00837     inline bool
00838     operator>=(const set<_Key, _Compare, _Alloc>& __x,
00839            const set<_Key, _Compare, _Alloc>& __y)
00840     { return !(__x < __y); }
00841 
00842   /// See std::set::swap().
00843   template<typename _Key, typename _Compare, typename _Alloc>
00844     inline void
00845     swap(set<_Key, _Compare, _Alloc>& __x, set<_Key, _Compare, _Alloc>& __y)
00846     { __x.swap(__y); }
00847 
00848 _GLIBCXX_END_NAMESPACE_CONTAINER
00849 } //namespace std
00850 #endif /* _STL_SET_H */