stl_multiset.h

来自「symbian上STL模板库的实现」· C头文件 代码 · 共 586 行 · 第 1/2 页

// Multiset implementation -*- C++ -*-

// Copyright (C) 2001, 2002, 2004 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING.  If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 * Copyright (c) 1996
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 */

/** @file stl_multiset.h
 *  This is an internal header file, included by other library headers.
 *  You should not attempt to use it directly.
 */

#ifndef _MULTISET_H
#define _MULTISET_H 1

#include <bits/concept_check.h>

namespace _GLIBCXX_STD
{

    // Forward declaration of operators < and ==, needed for friend declaration.
    template <class _Key, class _Compare = less<_Key>,
             class _Alloc = allocator<_Key> >
                 class multiset;

    template <class _Key, class _Compare, class _Alloc>
        inline bool
        operator==(const multiset<_Key,_Compare,_Alloc>& __x,
                const multiset<_Key,_Compare,_Alloc>& __y);

    template <class _Key, class _Compare, class _Alloc>
        inline bool
        operator<(const multiset<_Key,_Compare,_Alloc>& __x,
                const multiset<_Key,_Compare,_Alloc>& __y);

    /**
     *  @brief A standard container made up of elements, which can be retrieved
     *  in logarithmic time.
     *
     *  @ingroup Containers
     *  @ingroup Assoc_containers
     *
     *  Meets the requirements of a <a href="tables.html#65">container</a>, a
     *  <a href="tables.html#66">reversible container</a>, and an
     *  <a href="tables.html#69">associative container</a> (using equivalent
     *  keys).  For a @c multiset<Key> the key_type and value_type are Key.
     *
     *  Multisets support bidirectional iterators.
     *
     *  @if maint
     *  The private tree data is declared exactly the same way for set and
     *  multiset; the distinction is made entirely in how the tree functions are
     *  called (*_unique versus *_equal, same as the standard).
     *  @endif
     */
    template <class _Key, class _Compare, class _Alloc>
        class multiset
        {
            // concept requirements
            __glibcxx_class_requires(_Key, _SGIAssignableConcept)
                __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
                        _BinaryFunctionConcept)

            public:
                // typedefs:
                typedef _Key     key_type;
                typedef _Key     value_type;
                typedef _Compare key_compare;
                typedef _Compare value_compare;

            private:
                /// @if maint  This turns a red-black tree into a [multi]set.  @endif
                typedef _Rb_tree<key_type, value_type,
                        _Identity<value_type>, key_compare, _Alloc> _Rep_type;
                /// @if maint  The actual tree structure.  @endif
                _Rep_type _M_t;

            public:
                typedef typename _Alloc::pointer pointer;
                typedef typename _Alloc::const_pointer const_pointer;
                typedef typename _Alloc::reference reference;
                typedef typename _Alloc::const_reference const_reference;
                // _GLIBCXX_RESOLVE_LIB_DEFECTS
                // DR 103. set::iterator is required to be modifiable,
                // but this allows modification of keys.
                typedef typename _Rep_type::const_iterator iterator;
                typedef typename _Rep_type::const_iterator const_iterator;
                typedef typename _Rep_type::const_reverse_iterator reverse_iterator;
                typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
                typedef typename _Rep_type::size_type size_type;
                typedef typename _Rep_type::difference_type difference_type;
                typedef typename _Rep_type::allocator_type allocator_type;

                // allocation/deallocation

                /**
                 *  @brief  Default constructor creates no elements.
                 */
                multiset()
                    : _M_t(_Compare(), allocator_type()) { }

                explicit
                    multiset(const _Compare& __comp,
                            const allocator_type& __a = allocator_type())
                    : _M_t(__comp, __a) { }

                /**
                 *  @brief  Builds a %multiset from a range.
                 *  @param  first  An input iterator.
                 *  @param  last  An input iterator.
                 *
                 *  Create a %multiset consisting of copies of the elements from
                 *  [first,last).  This is linear in N if the range is already sorted,
                 *  and NlogN otherwise (where N is distance(first,last)).
                 */
                template <class _InputIterator>
                    multiset(_InputIterator __first, _InputIterator __last)
                    : _M_t(_Compare(), allocator_type())
                    { _M_t.insert_equal(__first, __last); }

                /**
                 *  @brief  Builds a %multiset from a range.
                 *  @param  first  An input iterator.
                 *  @param  last  An input iterator.
                 *  @param  comp  A comparison functor.
                 *  @param  a  An allocator object.
                 *
                 *  Create a %multiset consisting of copies of the elements from
                 *  [first,last).  This is linear in N if the range is already sorted,
                 *  and NlogN otherwise (where N is distance(first,last)).
                 */
                template <class _InputIterator>
                    multiset(_InputIterator __first, _InputIterator __last,
                            const _Compare& __comp,
                            const allocator_type& __a = allocator_type())
                    : _M_t(__comp, __a)
                    { _M_t.insert_equal(__first, __last); }

                /**
                 *  @brief  %Multiset copy constructor.
                 *  @param  x  A %multiset of identical element and allocator types.
                 *
                 *  The newly-created %multiset uses a copy of the allocation object used
                 *  by @a x.
                 */
                multiset(const multiset<_Key,_Compare,_Alloc>& __x)
                    : _M_t(__x._M_t) { }

                /**
                 *  @brief  %Multiset assignment operator.
                 *  @param  x  A %multiset of identical element and allocator types.
                 *
                 *  All the elements of @a x are copied, but unlike the copy constructor,
                 *  the allocator object is not copied.
                 */
                multiset<_Key,_Compare,_Alloc>&
                    operator=(const multiset<_Key,_Compare,_Alloc>& __x)
                    {
                        _M_t = __x._M_t;
                        return *this;
                    }

                // accessors:

                ///  Returns the comparison object.
                key_compare
                    key_comp() const
                    { return _M_t.key_comp(); }
                ///  Returns the comparison object.
                value_compare
                    value_comp() const
                    { return _M_t.key_comp(); }
                ///  Returns the memory allocation object.
                allocator_type
                    get_allocator() const
                    { return _M_t.get_allocator(); }

                /**
                 *  Returns a read/write iterator that points to the first element in the
                 *  %multiset.  Iteration is done in ascending order according to the
                 *  keys.
                 */
                iterator
                    begin() const
                    { return _M_t.begin(); }

                /**
                 *  Returns a read/write iterator that points one past the last element in
                 *  the %multiset.  Iteration is done in ascending order according to the
                 *  keys.
                 */
                iterator
                    end() const
                    { return _M_t.end(); }

                /**
                 *  Returns a read/write reverse iterator that points to the last element
                 *  in the %multiset.  Iteration is done in descending order according to
                 *  the keys.
                 */
                reverse_iterator
                    rbegin() const
                    { return _M_t.rbegin(); }

                /**
                 *  Returns a read/write reverse iterator that points to the last element
                 *  in the %multiset.  Iteration is done in descending order according to
                 *  the keys.
                 */
                reverse_iterator
                    rend() const
                    { return _M_t.rend(); }

                ///  Returns true if the %set is empty.
                bool
                    empty() const
                    { return _M_t.empty(); }

                ///  Returns the size of the %set.
                size_type
                    size() const
                    { return _M_t.size(); }

                ///  Returns the maximum size of the %set.
                size_type
                    max_size() const
                    { return _M_t.max_size(); }

                /**
                 *  @brief  Swaps data with another %multiset.
                 *  @param  x  A %multiset of the same element and allocator types.
                 *
                 *  This exchanges the elements between two multisets in constant time.
                 *  (It is only swapping a pointer, an integer, and an instance of the @c
                 *  Compare type (which itself is often stateless and empty), so it should
                 *  be quite fast.)
                 *  Note that the global std::swap() function is specialized such that
                 *  std::swap(s1,s2) will feed to this function.
                 */
                void
                    swap(multiset<_Key,_Compare,_Alloc>& __x)
                    { _M_t.swap(__x._M_t); }

                // insert/erase
                /**