libstdc++
stl_set.h
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00001 // Set implementation -*- C++ -*-
00002 
00003 // Copyright (C) 2001-2015 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 #if __cplusplus >= 201103L
00144       noexcept(is_nothrow_default_constructible<allocator_type>::value)
00145 #endif
00146       : _M_t() { }
00147 
00148       /**
00149        *  @brief  Creates a %set with no elements.
00150        *  @param  __comp  Comparator to use.
00151        *  @param  __a  An allocator object.
00152        */
00153       explicit
00154       set(const _Compare& __comp,
00155           const allocator_type& __a = allocator_type())
00156       : _M_t(__comp, _Key_alloc_type(__a)) { }
00157 
00158       /**
00159        *  @brief  Builds a %set from a range.
00160        *  @param  __first  An input iterator.
00161        *  @param  __last  An input iterator.
00162        *
00163        *  Create a %set consisting of copies of the elements from
00164        *  [__first,__last).  This is linear in N if the range is
00165        *  already sorted, and NlogN otherwise (where N is
00166        *  distance(__first,__last)).
00167        */
00168       template<typename _InputIterator>
00169         set(_InputIterator __first, _InputIterator __last)
00170         : _M_t()
00171         { _M_t._M_insert_unique(__first, __last); }
00172 
00173       /**
00174        *  @brief  Builds a %set from a range.
00175        *  @param  __first  An input iterator.
00176        *  @param  __last  An input iterator.
00177        *  @param  __comp  A comparison functor.
00178        *  @param  __a  An allocator object.
00179        *
00180        *  Create a %set consisting of copies of the elements from
00181        *  [__first,__last).  This is linear in N if the range is
00182        *  already sorted, and NlogN otherwise (where N is
00183        *  distance(__first,__last)).
00184        */
00185       template<typename _InputIterator>
00186         set(_InputIterator __first, _InputIterator __last,
00187             const _Compare& __comp,
00188             const allocator_type& __a = allocator_type())
00189         : _M_t(__comp, _Key_alloc_type(__a))
00190         { _M_t._M_insert_unique(__first, __last); }
00191 
00192       /**
00193        *  @brief  %Set copy constructor.
00194        *  @param  __x  A %set of identical element and allocator types.
00195        *
00196        *  The newly-created %set uses a copy of the allocation object used
00197        *  by @a __x.
00198        */
00199       set(const set& __x)
00200       : _M_t(__x._M_t) { }
00201 
00202 #if __cplusplus >= 201103L
00203      /**
00204        *  @brief %Set move constructor
00205        *  @param __x  A %set of identical element and allocator types.
00206        *
00207        *  The newly-created %set contains the exact contents of @a x.
00208        *  The contents of @a x are a valid, but unspecified %set.
00209        */
00210       set(set&& __x)
00211       noexcept(is_nothrow_copy_constructible<_Compare>::value)
00212       : _M_t(std::move(__x._M_t)) { }
00213 
00214       /**
00215        *  @brief  Builds a %set from an initializer_list.
00216        *  @param  __l  An initializer_list.
00217        *  @param  __comp  A comparison functor.
00218        *  @param  __a  An allocator object.
00219        *
00220        *  Create a %set consisting of copies of the elements in the list.
00221        *  This is linear in N if the list is already sorted, and NlogN
00222        *  otherwise (where N is @a __l.size()).
00223        */
00224       set(initializer_list<value_type> __l,
00225           const _Compare& __comp = _Compare(),
00226           const allocator_type& __a = allocator_type())
00227       : _M_t(__comp, _Key_alloc_type(__a))
00228       { _M_t._M_insert_unique(__l.begin(), __l.end()); }
00229 
00230       /// Allocator-extended default constructor.
00231       explicit
00232       set(const allocator_type& __a)
00233       : _M_t(_Compare(), _Key_alloc_type(__a)) { }
00234 
00235       /// Allocator-extended copy constructor.
00236       set(const set& __x, const allocator_type& __a)
00237       : _M_t(__x._M_t, _Key_alloc_type(__a)) { }
00238 
00239       /// Allocator-extended move constructor.
00240       set(set&& __x, const allocator_type& __a)
00241       noexcept(is_nothrow_copy_constructible<_Compare>::value
00242                && _Alloc_traits::_S_always_equal())
00243       : _M_t(std::move(__x._M_t), _Key_alloc_type(__a)) { }
00244 
00245       /// Allocator-extended initialier-list constructor.
00246       set(initializer_list<value_type> __l, const allocator_type& __a)
00247       : _M_t(_Compare(), _Key_alloc_type(__a))
00248       { _M_t._M_insert_unique(__l.begin(), __l.end()); }
00249 
00250       /// Allocator-extended range constructor.
00251       template<typename _InputIterator>
00252         set(_InputIterator __first, _InputIterator __last,
00253             const allocator_type& __a)
00254         : _M_t(_Compare(), _Key_alloc_type(__a))
00255         { _M_t._M_insert_unique(__first, __last); }
00256 #endif
00257 
00258       /**
00259        *  @brief  %Set assignment operator.
00260        *  @param  __x  A %set of identical element and allocator types.
00261        *
00262        *  All the elements of @a __x are copied, but unlike the copy
00263        *  constructor, the allocator object is not copied.
00264        */
00265       set&
00266       operator=(const set& __x)
00267       {
00268         _M_t = __x._M_t;
00269         return *this;
00270       }
00271 
00272 #if __cplusplus >= 201103L
00273       /// Move assignment operator.
00274       set&
00275       operator=(set&&) = default;
00276 
00277       /**
00278        *  @brief  %Set list assignment operator.
00279        *  @param  __l  An initializer_list.
00280        *
00281        *  This function fills a %set with copies of the elements in the
00282        *  initializer list @a __l.
00283        *
00284        *  Note that the assignment completely changes the %set and
00285        *  that the resulting %set's size is the same as the number
00286        *  of elements assigned.  Old data may be lost.
00287        */
00288       set&
00289       operator=(initializer_list<value_type> __l)
00290       {
00291         _M_t._M_assign_unique(__l.begin(), __l.end());
00292         return *this;
00293       }
00294 #endif
00295 
00296       // accessors:
00297 
00298       ///  Returns the comparison object with which the %set was constructed.
00299       key_compare
00300       key_comp() const
00301       { return _M_t.key_comp(); }
00302       ///  Returns the comparison object with which the %set was constructed.
00303       value_compare
00304       value_comp() const
00305       { return _M_t.key_comp(); }
00306       ///  Returns the allocator object with which the %set was constructed.
00307       allocator_type
00308       get_allocator() const _GLIBCXX_NOEXCEPT
00309       { return allocator_type(_M_t.get_allocator()); }
00310 
00311       /**
00312        *  Returns a read-only (constant) iterator that points to the first
00313        *  element in the %set.  Iteration is done in ascending order according
00314        *  to the keys.
00315        */
00316       iterator
00317       begin() const _GLIBCXX_NOEXCEPT
00318       { return _M_t.begin(); }
00319 
00320       /**
00321        *  Returns a read-only (constant) iterator that points one past the last
00322        *  element in the %set.  Iteration is done in ascending order according
00323        *  to the keys.
00324        */
00325       iterator
00326       end() const _GLIBCXX_NOEXCEPT
00327       { return _M_t.end(); }
00328 
00329       /**
00330        *  Returns a read-only (constant) iterator that points to the last
00331        *  element in the %set.  Iteration is done in descending order according
00332        *  to the keys.
00333        */
00334       reverse_iterator
00335       rbegin() const _GLIBCXX_NOEXCEPT
00336       { return _M_t.rbegin(); }
00337 
00338       /**
00339        *  Returns a read-only (constant) reverse iterator that points to the
00340        *  last pair in the %set.  Iteration is done in descending order
00341        *  according to the keys.
00342        */
00343       reverse_iterator
00344       rend() const _GLIBCXX_NOEXCEPT
00345       { return _M_t.rend(); }
00346 
00347 #if __cplusplus >= 201103L
00348       /**
00349        *  Returns a read-only (constant) iterator that points to the first
00350        *  element in the %set.  Iteration is done in ascending order according
00351        *  to the keys.
00352        */
00353       iterator
00354       cbegin() const noexcept
00355       { return _M_t.begin(); }
00356 
00357       /**
00358        *  Returns a read-only (constant) iterator that points one past the last
00359        *  element in the %set.  Iteration is done in ascending order according
00360        *  to the keys.
00361        */
00362       iterator
00363       cend() const noexcept
00364       { return _M_t.end(); }
00365 
00366       /**
00367        *  Returns a read-only (constant) iterator that points to the last
00368        *  element in the %set.  Iteration is done in descending order according
00369        *  to the keys.
00370        */
00371       reverse_iterator
00372       crbegin() const noexcept
00373       { return _M_t.rbegin(); }
00374 
00375       /**
00376        *  Returns a read-only (constant) reverse iterator that points to the
00377        *  last pair in the %set.  Iteration is done in descending order
00378        *  according to the keys.
00379        */
00380       reverse_iterator
00381       crend() const noexcept
00382       { return _M_t.rend(); }
00383 #endif
00384 
00385       ///  Returns true if the %set is empty.
00386       bool
00387       empty() const _GLIBCXX_NOEXCEPT
00388       { return _M_t.empty(); }
00389 
00390       ///  Returns the size of the %set.
00391       size_type
00392       size() const _GLIBCXX_NOEXCEPT
00393       { return _M_t.size(); }
00394 
00395       ///  Returns the maximum size of the %set.
00396       size_type
00397       max_size() const _GLIBCXX_NOEXCEPT
00398       { return _M_t.max_size(); }
00399 
00400       /**
00401        *  @brief  Swaps data with another %set.
00402        *  @param  __x  A %set of the same element and allocator types.
00403        *
00404        *  This exchanges the elements between two sets in constant
00405        *  time.  (It is only swapping a pointer, an integer, and an
00406        *  instance of the @c Compare type (which itself is often
00407        *  stateless and empty), so it should be quite fast.)  Note
00408        *  that the global std::swap() function is specialized such
00409        *  that std::swap(s1,s2) will feed to this function.
00410        */
00411       void
00412       swap(set& __x)
00413 #if __cplusplus >= 201103L
00414       noexcept(_Alloc_traits::_S_nothrow_swap())
00415 #endif
00416       { _M_t.swap(__x._M_t); }
00417 
00418       // insert/erase
00419 #if __cplusplus >= 201103L
00420       /**
00421        *  @brief Attempts to build and insert an element into the %set.
00422        *  @param __args  Arguments used to generate an element.
00423        *  @return  A pair, of which the first element is an iterator that points
00424        *           to the possibly inserted element, and the second is a bool
00425        *           that is true if the element was actually inserted.
00426        *
00427        *  This function attempts to build and insert an element into the %set.
00428        *  A %set relies on unique keys and thus an element is only inserted if
00429        *  it is not already present in the %set.
00430        *
00431        *  Insertion requires logarithmic time.
00432        */
00433       template<typename... _Args>
00434         std::pair<iterator, bool>
00435         emplace(_Args&&... __args)
00436         { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
00437 
00438       /**
00439        *  @brief Attempts to insert an element into the %set.
00440        *  @param  __pos  An iterator that serves as a hint as to where the
00441        *                element should be inserted.
00442        *  @param  __args  Arguments used to generate the element to be
00443        *                 inserted.
00444        *  @return An iterator that points to the element with key equivalent to
00445        *          the one generated from @a __args (may or may not be the
00446        *          element itself).
00447        *
00448        *  This function is not concerned about whether the insertion took place,
00449        *  and thus does not return a boolean like the single-argument emplace()
00450        *  does.  Note that the first parameter is only a hint and can
00451        *  potentially improve the performance of the insertion process.  A bad
00452        *  hint would cause no gains in efficiency.
00453        *
00454        *  For more on @a hinting, see:
00455        *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
00456        *
00457        *  Insertion requires logarithmic time (if the hint is not taken).
00458        */
00459       template<typename... _Args>
00460         iterator
00461         emplace_hint(const_iterator __pos, _Args&&... __args)
00462         {
00463           return _M_t._M_emplace_hint_unique(__pos,
00464                                              std::forward<_Args>(__args)...);
00465         }
00466 #endif
00467 
00468       /**
00469        *  @brief Attempts to insert an element into the %set.
00470        *  @param  __x  Element to be inserted.
00471        *  @return  A pair, of which the first element is an iterator that points
00472        *           to the possibly inserted element, and the second is a bool
00473        *           that is true if the element was actually inserted.
00474        *
00475        *  This function attempts to insert an element into the %set.  A %set
00476        *  relies on unique keys and thus an element is only inserted if it is
00477        *  not already present in the %set.
00478        *
00479        *  Insertion requires logarithmic time.
00480        */
00481       std::pair<iterator, bool>
00482       insert(const value_type& __x)
00483       {
00484         std::pair<typename _Rep_type::iterator, bool> __p =
00485           _M_t._M_insert_unique(__x);
00486         return std::pair<iterator, bool>(__p.first, __p.second);
00487       }
00488 
00489 #if __cplusplus >= 201103L
00490       std::pair<iterator, bool>
00491       insert(value_type&& __x)
00492       {
00493         std::pair<typename _Rep_type::iterator, bool> __p =
00494           _M_t._M_insert_unique(std::move(__x));
00495         return std::pair<iterator, bool>(__p.first, __p.second);
00496       }
00497 #endif
00498 
00499       /**
00500        *  @brief Attempts to insert an element into the %set.
00501        *  @param  __position  An iterator that serves as a hint as to where the
00502        *                    element should be inserted.
00503        *  @param  __x  Element to be inserted.
00504        *  @return An iterator that points to the element with key of
00505        *           @a __x (may or may not be the element passed in).
00506        *
00507        *  This function is not concerned about whether the insertion took place,
00508        *  and thus does not return a boolean like the single-argument insert()
00509        *  does.  Note that the first parameter is only a hint and can
00510        *  potentially improve the performance of the insertion process.  A bad
00511        *  hint would cause no gains in efficiency.
00512        *
00513        *  For more on @a hinting, see:
00514        *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
00515        *
00516        *  Insertion requires logarithmic time (if the hint is not taken).
00517        */
00518       iterator
00519       insert(const_iterator __position, const value_type& __x)
00520       { return _M_t._M_insert_unique_(__position, __x); }
00521 
00522 #if __cplusplus >= 201103L
00523       iterator
00524       insert(const_iterator __position, value_type&& __x)
00525       { return _M_t._M_insert_unique_(__position, std::move(__x)); }
00526 #endif
00527 
00528       /**
00529        *  @brief A template function that attempts to insert a range
00530        *  of elements.
00531        *  @param  __first  Iterator pointing to the start of the range to be
00532        *                   inserted.
00533        *  @param  __last  Iterator pointing to the end of the range.
00534        *
00535        *  Complexity similar to that of the range constructor.
00536        */
00537       template<typename _InputIterator>
00538         void
00539         insert(_InputIterator __first, _InputIterator __last)
00540         { _M_t._M_insert_unique(__first, __last); }
00541 
00542 #if __cplusplus >= 201103L
00543       /**
00544        *  @brief Attempts to insert a list of elements into the %set.
00545        *  @param  __l  A std::initializer_list<value_type> of elements
00546        *               to be inserted.
00547        *
00548        *  Complexity similar to that of the range constructor.
00549        */
00550       void
00551       insert(initializer_list<value_type> __l)
00552       { this->insert(__l.begin(), __l.end()); }
00553 #endif
00554 
00555 #if __cplusplus >= 201103L
00556       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00557       // DR 130. Associative erase should return an iterator.
00558       /**
00559        *  @brief Erases an element from a %set.
00560        *  @param  __position  An iterator pointing to the element to be erased.
00561        *  @return An iterator pointing to the element immediately following
00562        *          @a __position prior to the element being erased. If no such
00563        *          element exists, end() is returned.
00564        *
00565        *  This function erases an element, pointed to by the given iterator,
00566        *  from a %set.  Note that this function only erases the element, and
00567        *  that if the element is itself a pointer, the pointed-to memory is not
00568        *  touched in any way.  Managing the pointer is the user's
00569        *  responsibility.
00570        */
00571       _GLIBCXX_ABI_TAG_CXX11
00572       iterator
00573       erase(const_iterator __position)
00574       { return _M_t.erase(__position); }
00575 #else
00576       /**
00577        *  @brief Erases an element from a %set.
00578        *  @param  position  An iterator pointing to the element to be erased.
00579        *
00580        *  This function erases an element, pointed to by the given iterator,
00581        *  from a %set.  Note that this function only erases the element, and
00582        *  that if the element is itself a pointer, the pointed-to memory is not
00583        *  touched in any way.  Managing the pointer is the user's
00584        *  responsibility.
00585        */
00586       void
00587       erase(iterator __position)
00588       { _M_t.erase(__position); }
00589 #endif
00590 
00591       /**
00592        *  @brief Erases elements according to the provided key.
00593        *  @param  __x  Key of element to be erased.
00594        *  @return  The number of elements erased.
00595        *
00596        *  This function erases all the elements located by the given key from
00597        *  a %set.
00598        *  Note that this function only erases the element, and that if
00599        *  the element is itself a pointer, the pointed-to memory is not touched
00600        *  in any way.  Managing the pointer is the user's responsibility.
00601        */
00602       size_type
00603       erase(const key_type& __x)
00604       { return _M_t.erase(__x); }
00605 
00606 #if __cplusplus >= 201103L
00607       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00608       // DR 130. Associative erase should return an iterator.
00609       /**
00610        *  @brief Erases a [__first,__last) range of elements from a %set.
00611        *  @param  __first  Iterator pointing to the start of the range to be
00612        *                 erased.
00613 
00614        *  @param __last Iterator pointing to the end of the range to
00615        *  be erased.
00616        *  @return The iterator @a __last.
00617        *
00618        *  This function erases a sequence of elements from a %set.
00619        *  Note that this function only erases the element, and that if
00620        *  the element is itself a pointer, the pointed-to memory is not touched
00621        *  in any way.  Managing the pointer is the user's responsibility.
00622        */
00623       _GLIBCXX_ABI_TAG_CXX11
00624       iterator
00625       erase(const_iterator __first, const_iterator __last)
00626       { return _M_t.erase(__first, __last); }
00627 #else
00628       /**
00629        *  @brief Erases a [first,last) range of elements from a %set.
00630        *  @param  __first  Iterator pointing to the start of the range to be
00631        *                 erased.
00632        *  @param __last Iterator pointing to the end of the range to
00633        *  be erased.
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       void
00641       erase(iterator __first, iterator __last)
00642       { _M_t.erase(__first, __last); }
00643 #endif
00644 
00645       /**
00646        *  Erases all elements in a %set.  Note that this function only erases
00647        *  the elements, and that if the elements themselves are pointers, the
00648        *  pointed-to memory is not touched in any way.  Managing the pointer is
00649        *  the user's responsibility.
00650        */
00651       void
00652       clear() _GLIBCXX_NOEXCEPT
00653       { _M_t.clear(); }
00654 
00655       // set operations:
00656 
00657       //@{
00658       /**
00659        *  @brief  Finds the number of elements.
00660        *  @param  __x  Element to located.
00661        *  @return  Number of elements with specified key.
00662        *
00663        *  This function only makes sense for multisets; for set the result will
00664        *  either be 0 (not present) or 1 (present).
00665        */
00666       size_type
00667       count(const key_type& __x) const
00668       { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
00669 
00670 #if __cplusplus > 201103L
00671       template<typename _Kt>
00672         auto
00673         count(const _Kt& __x) const
00674         -> decltype(_M_t._M_count_tr(__x))
00675         { return _M_t._M_find_tr(__x) == _M_t.end() ? 0 : 1; }
00676 #endif
00677       //@}
00678 
00679       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00680       // 214.  set::find() missing const overload
00681       //@{
00682       /**
00683        *  @brief Tries to locate an element in a %set.
00684        *  @param  __x  Element to be located.
00685        *  @return  Iterator pointing to sought-after element, or end() if not
00686        *           found.
00687        *
00688        *  This function takes a key and tries to locate the element with which
00689        *  the key matches.  If successful the function returns an iterator
00690        *  pointing to the sought after element.  If unsuccessful it returns the
00691        *  past-the-end ( @c end() ) iterator.
00692        */
00693       iterator
00694       find(const key_type& __x)
00695       { return _M_t.find(__x); }
00696 
00697       const_iterator
00698       find(const key_type& __x) const
00699       { return _M_t.find(__x); }
00700 
00701 #if __cplusplus > 201103L
00702       template<typename _Kt>
00703         auto
00704         find(const _Kt& __x)
00705         -> decltype(iterator{_M_t._M_find_tr(__x)})
00706         { return iterator{_M_t._M_find_tr(__x)}; }
00707 
00708       template<typename _Kt>
00709         auto
00710         find(const _Kt& __x) const
00711         -> decltype(const_iterator{_M_t._M_find_tr(__x)})
00712         { return const_iterator{_M_t._M_find_tr(__x)}; }
00713 #endif
00714       //@}
00715 
00716       //@{
00717       /**
00718        *  @brief Finds the beginning of a subsequence matching given key.
00719        *  @param  __x  Key to be located.
00720        *  @return  Iterator pointing to first element equal to or greater
00721        *           than key, or end().
00722        *
00723        *  This function returns the first element of a subsequence of elements
00724        *  that matches the given key.  If unsuccessful it returns an iterator
00725        *  pointing to the first element that has a greater value than given key
00726        *  or end() if no such element exists.
00727        */
00728       iterator
00729       lower_bound(const key_type& __x)
00730       { return _M_t.lower_bound(__x); }
00731 
00732       const_iterator
00733       lower_bound(const key_type& __x) const
00734       { return _M_t.lower_bound(__x); }
00735 
00736 #if __cplusplus > 201103L
00737       template<typename _Kt>
00738         auto
00739         lower_bound(const _Kt& __x)
00740         -> decltype(_M_t._M_lower_bound_tr(__x))
00741         { return _M_t._M_lower_bound_tr(__x); }
00742 
00743       template<typename _Kt>
00744         auto
00745         lower_bound(const _Kt& __x) const
00746         -> decltype(_M_t._M_lower_bound_tr(__x))
00747         { return _M_t._M_lower_bound_tr(__x); }
00748 #endif
00749       //@}
00750 
00751       //@{
00752       /**
00753        *  @brief Finds the end of a subsequence matching given key.
00754        *  @param  __x  Key to be located.
00755        *  @return Iterator pointing to the first element
00756        *          greater than key, or end().
00757        */
00758       iterator
00759       upper_bound(const key_type& __x)
00760       { return _M_t.upper_bound(__x); }
00761 
00762       const_iterator
00763       upper_bound(const key_type& __x) const
00764       { return _M_t.upper_bound(__x); }
00765 
00766 #if __cplusplus > 201103L
00767       template<typename _Kt>
00768         auto
00769         upper_bound(const _Kt& __x)
00770         -> decltype(_M_t._M_upper_bound_tr(__x))
00771         { return _M_t._M_upper_bound_tr(__x); }
00772 
00773       template<typename _Kt>
00774         auto
00775         upper_bound(const _Kt& __x) const
00776         -> decltype(_M_t._M_upper_bound_tr(__x))
00777         { return _M_t._M_upper_bound_tr(__x); }
00778 #endif
00779       //@}
00780 
00781       //@{
00782       /**
00783        *  @brief Finds a subsequence matching given key.
00784        *  @param  __x  Key to be located.
00785        *  @return  Pair of iterators that possibly points to the subsequence
00786        *           matching given key.
00787        *
00788        *  This function is equivalent to
00789        *  @code
00790        *    std::make_pair(c.lower_bound(val),
00791        *                   c.upper_bound(val))
00792        *  @endcode
00793        *  (but is faster than making the calls separately).
00794        *
00795        *  This function probably only makes sense for multisets.
00796        */
00797       std::pair<iterator, iterator>
00798       equal_range(const key_type& __x)
00799       { return _M_t.equal_range(__x); }
00800 
00801       std::pair<const_iterator, const_iterator>
00802       equal_range(const key_type& __x) const
00803       { return _M_t.equal_range(__x); }
00804 
00805 #if __cplusplus > 201103L
00806       template<typename _Kt>
00807         auto
00808         equal_range(const _Kt& __x)
00809         -> decltype(_M_t._M_equal_range_tr(__x))
00810         { return _M_t._M_equal_range_tr(__x); }
00811 
00812       template<typename _Kt>
00813         auto
00814         equal_range(const _Kt& __x) const
00815         -> decltype(_M_t._M_equal_range_tr(__x))
00816         { return _M_t._M_equal_range_tr(__x); }
00817 #endif
00818       //@}
00819 
00820       template<typename _K1, typename _C1, typename _A1>
00821         friend bool
00822         operator==(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
00823 
00824       template<typename _K1, typename _C1, typename _A1>
00825         friend bool
00826         operator<(const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
00827     };
00828 
00829 
00830   /**
00831    *  @brief  Set equality comparison.
00832    *  @param  __x  A %set.
00833    *  @param  __y  A %set of the same type as @a x.
00834    *  @return  True iff the size and elements of the sets are equal.
00835    *
00836    *  This is an equivalence relation.  It is linear in the size of the sets.
00837    *  Sets are considered equivalent if their sizes are equal, and if
00838    *  corresponding elements compare equal.
00839   */
00840   template<typename _Key, typename _Compare, typename _Alloc>
00841     inline bool
00842     operator==(const set<_Key, _Compare, _Alloc>& __x,
00843                const set<_Key, _Compare, _Alloc>& __y)
00844     { return __x._M_t == __y._M_t; }
00845 
00846   /**
00847    *  @brief  Set ordering relation.
00848    *  @param  __x  A %set.
00849    *  @param  __y  A %set of the same type as @a x.
00850    *  @return  True iff @a __x is lexicographically less than @a __y.
00851    *
00852    *  This is a total ordering relation.  It is linear in the size of the
00853    *  sets.  The elements must be comparable with @c <.
00854    *
00855    *  See std::lexicographical_compare() for how the determination is made.
00856   */
00857   template<typename _Key, typename _Compare, typename _Alloc>
00858     inline bool
00859     operator<(const set<_Key, _Compare, _Alloc>& __x,
00860               const set<_Key, _Compare, _Alloc>& __y)
00861     { return __x._M_t < __y._M_t; }
00862 
00863   ///  Returns !(x == y).
00864   template<typename _Key, typename _Compare, typename _Alloc>
00865     inline bool
00866     operator!=(const set<_Key, _Compare, _Alloc>& __x,
00867                const set<_Key, _Compare, _Alloc>& __y)
00868     { return !(__x == __y); }
00869 
00870   ///  Returns y < x.
00871   template<typename _Key, typename _Compare, typename _Alloc>
00872     inline bool
00873     operator>(const set<_Key, _Compare, _Alloc>& __x,
00874               const set<_Key, _Compare, _Alloc>& __y)
00875     { return __y < __x; }
00876 
00877   ///  Returns !(y < x)
00878   template<typename _Key, typename _Compare, typename _Alloc>
00879     inline bool
00880     operator<=(const set<_Key, _Compare, _Alloc>& __x,
00881                const set<_Key, _Compare, _Alloc>& __y)
00882     { return !(__y < __x); }
00883 
00884   ///  Returns !(x < y)
00885   template<typename _Key, typename _Compare, typename _Alloc>
00886     inline bool
00887     operator>=(const set<_Key, _Compare, _Alloc>& __x,
00888                const set<_Key, _Compare, _Alloc>& __y)
00889     { return !(__x < __y); }
00890 
00891   /// See std::set::swap().
00892   template<typename _Key, typename _Compare, typename _Alloc>
00893     inline void
00894     swap(set<_Key, _Compare, _Alloc>& __x, set<_Key, _Compare, _Alloc>& __y)
00895     { __x.swap(__y); }
00896 
00897 _GLIBCXX_END_NAMESPACE_CONTAINER
00898 } //namespace std
00899 #endif /* _STL_SET_H */