stl_multiset.h
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// Multiset implementation -*- C++ -*-
// Copyright (C) 2001-2013 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 3, 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.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/*
*
* 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 bits/stl_multiset.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{set}
*/
#ifndef _STL_MULTISET_H
#define _STL_MULTISET_H 1
#include <bits/concept_check.h>
#if __cplusplus >= 201103L
#include <initializer_list>
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
/**
* @brief A standard container made up of elements, which can be retrieved
* in logarithmic time.
*
* @ingroup associative_containers
*
*
* @tparam _Key Type of key objects.
* @tparam _Compare Comparison function object type, defaults to less<_Key>.
* @tparam _Alloc Allocator type, defaults to allocator<_Key>.
*
* 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.
*
* 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).
*/
template <typename _Key, typename _Compare = std::less<_Key>,
typename _Alloc = std::allocator<_Key> >
class multiset
{
// concept requirements
typedef typename _Alloc::value_type _Alloc_value_type;
__glibcxx_class_requires(_Key, _SGIAssignableConcept)
__glibcxx_class_requires4(_Compare, bool, _Key, _Key,
_BinaryFunctionConcept)
__glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept)
public:
// typedefs:
typedef _Key key_type;
typedef _Key value_type;
typedef _Compare key_compare;
typedef _Compare value_compare;
typedef _Alloc allocator_type;
private:
/// This turns a red-black tree into a [multi]set.
typedef typename _Alloc::template rebind<_Key>::other _Key_alloc_type;
typedef _Rb_tree<key_type, value_type, _Identity<value_type>,
key_compare, _Key_alloc_type> _Rep_type;
/// The actual tree structure.
_Rep_type _M_t;
public:
typedef typename _Key_alloc_type::pointer pointer;
typedef typename _Key_alloc_type::const_pointer const_pointer;
typedef typename _Key_alloc_type::reference reference;
typedef typename _Key_alloc_type::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;
// allocation/deallocation
/**
* @brief Default constructor creates no elements.
*/
multiset()
: _M_t() { }
/**
* @brief Creates a %multiset with no elements.
* @param __comp Comparator to use.
* @param __a An allocator object.
*/
explicit
multiset(const _Compare& __comp,
const allocator_type& __a = allocator_type())
: _M_t(__comp, _Key_alloc_type(__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<typename _InputIterator>
multiset(_InputIterator __first, _InputIterator __last)
: _M_t()
{ _M_t._M_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<typename _InputIterator>
multiset(_InputIterator __first, _InputIterator __last,
const _Compare& __comp,
const allocator_type& __a = allocator_type())
: _M_t(__comp, _Key_alloc_type(__a))
{ _M_t._M_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& __x)
: _M_t(__x._M_t) { }
#if __cplusplus >= 201103L
/**
* @brief %Multiset move constructor.
* @param __x A %multiset of identical element and allocator types.
*
* The newly-created %multiset contains the exact contents of @a __x.
* The contents of @a __x are a valid, but unspecified %multiset.
*/
multiset(multiset&& __x)
noexcept(is_nothrow_copy_constructible<_Compare>::value)
: _M_t(std::move(__x._M_t)) { }
/**
* @brief Builds a %multiset from an initializer_list.
* @param __l An initializer_list.
* @param __comp A comparison functor.
* @param __a An allocator object.
*
* Create a %multiset consisting of copies of the elements from
* the list. This is linear in N if the list is already sorted,
* and NlogN otherwise (where N is @a __l.size()).
*/
multiset(initializer_list<value_type> __l,
const _Compare& __comp = _Compare(),
const allocator_type& __a = allocator_type())
: _M_t(__comp, _Key_alloc_type(__a))
{ _M_t._M_insert_equal(__l.begin(), __l.end()); }
#endif
/**
* @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&
operator=(const multiset& __x)
{
_M_t = __x._M_t;
return *this;
}
#if __cplusplus >= 201103L
/**
* @brief %Multiset move assignment operator.
* @param __x A %multiset of identical element and allocator types.
*
* The contents of @a __x are moved into this %multiset
* (without copying). @a __x is a valid, but unspecified
* %multiset.
*/
multiset&
operator=(multiset&& __x)
{
// NB: DR 1204.
// NB: DR 675.
this->clear();
this->swap(__x);
return *this;
}
/**
* @brief %Multiset list assignment operator.
* @param __l An initializer_list.
*
* This function fills a %multiset with copies of the elements in the
* initializer list @a __l.
*
* Note that the assignment completely changes the %multiset and
* that the resulting %multiset's size is the same as the number
* of elements assigned. Old data may be lost.
*/
multiset&
operator=(initializer_list<value_type> __l)
{
this->clear();
this->insert(__l.begin(), __l.end());
return *this;
}
#endif
// 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 _GLIBCXX_NOEXCEPT
{ return allocator_type(_M_t.get_allocator()); }
/**
* Returns a read-only (constant) iterator that points to the first
* element in the %multiset. Iteration is done in ascending order
* according to the keys.
*/
iterator
begin() const _GLIBCXX_NOEXCEPT
{ return _M_t.begin(); }
/**
* Returns a read-only (constant) iterator that points one past the last
* element in the %multiset. Iteration is done in ascending order
* according to the keys.
*/
iterator
end() const _GLIBCXX_NOEXCEPT
{ return _M_t.end(); }
/**
* Returns a read-only (constant) 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 _GLIBCXX_NOEXCEPT
{ return _M_t.rbegin(); }
/**
* Returns a read-only (constant) 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 _GLIBCXX_NOEXCEPT
{ return _M_t.rend(); }
#if __cplusplus >= 201103L
/**
* Returns a read-only (constant) iterator that points to the first
* element in the %multiset. Iteration is done in ascending order
* according to the keys.
*/
iterator
cbegin() const noexcept
{ return _M_t.begin(); }
/**
* Returns a read-only (constant) iterator that points one past the last
* element in the %multiset. Iteration is done in ascending order
* according to the keys.
*/
iterator
cend() const noexcept
{ return _M_t.end(); }
/**
* Returns a read-only (constant) reverse iterator that points to the
* last element in the %multiset. Iteration is done in descending order
* according to the keys.
*/
reverse_iterator
crbegin() const noexcept
{ return _M_t.rbegin(); }
/**
* Returns a read-only (constant) reverse iterator that points to the
* last element in the %multiset. Iteration is done in descending order
* according to the keys.
*/
reverse_iterator
crend() const noexcept
{ return _M_t.rend(); }
#endif
/// Returns true if the %set is empty.
bool
empty() const _GLIBCXX_NOEXCEPT
{ return _M_t.empty(); }
/// Returns the size of the %set.
size_type
size() const _GLIBCXX_NOEXCEPT
{ return _M_t.size(); }
/// Returns the maximum size of the %set.
size_type
max_size() const _GLIBCXX_NOEXCEPT
{ 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& __x)
{ _M_t.swap(__x._M_t); }
// insert/erase
#if __cplusplus >= 201103L
/**
* @brief Builds and inserts an element into the %multiset.
* @param __args Arguments used to generate the element instance to be
* inserted.
* @return An iterator that points to the inserted element.
*
* This function inserts an element into the %multiset. Contrary
* to a std::set the %multiset does not rely on unique keys and thus
* multiple copies of the same element can be inserted.
*
* Insertion requires logarithmic time.
*/
template<typename... _Args>
iterator
emplace(_Args&&... __args)
{ return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); }
/**
* @brief Builds and inserts an element into the %multiset.
* @param __pos An iterator that serves as a hint as to where the
* element should be inserted.
* @param __args Arguments used to generate the element instance to be
* inserted.
* @return An iterator that points to the inserted element.
*
* This function inserts an element into the %multiset. Contrary
* to a std::set the %multiset does not rely on unique keys and thus
* multiple copies of the same element can be inserted.
*
* Note that the first parameter is only a hint and can potentially
* improve the performance of the insertion process. A bad hint would
* cause no gains in efficiency.
*
* See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
* for more on @a hinting.
*
* Insertion requires logarithmic time (if the hint is not taken).
*/
template<typename... _Args>
iterator
emplace_hint(const_iterator __pos, _Args&&... __args)
{
return _M_t._M_emplace_hint_equal(__pos,
std::forward<_Args>(__args)...);
}
#endif
/**
* @brief Inserts an element into the %multiset.
* @param __x Element to be inserted.
* @return An iterator that points to the inserted element.
*
* This function inserts an element into the %multiset. Contrary
* to a std::set the %multiset does not rely on unique keys and thus
* multiple copies of the same element can be inserted.
*
* Insertion requires logarithmic time.
*/
iterator
insert(const value_type& __x)
{ return _M_t._M_insert_equal(__x); }
#if __cplusplus >= 201103L
iterator
insert(value_type&& __x)
{ return _M_t._M_insert_equal(std::move(__x)); }
#endif
/**
* @brief Inserts an element into the %multiset.
* @param __position An iterator that serves as a hint as to where the
* element should be inserted.
* @param __x Element to be inserted.
* @return An iterator that points to the inserted element.
*
* This function inserts an element into the %multiset. Contrary
* to a std::set the %multiset does not rely on unique keys and thus
* multiple copies of the same element can be inserted.
*
* Note that the first parameter is only a hint and can potentially
* improve the performance of the insertion process. A bad hint would
* cause no gains in efficiency.
*
* See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
* for more on @a hinting.
*
* Insertion requires logarithmic time (if the hint is not taken).
*/
iterator
insert(const_iterator __position, const value_type& __x)
{ return _M_t._M_insert_equal_(__position, __x); }
#if __cplusplus >= 201103L
iterator
insert(const_iterator __position, value_type&& __x)
{ return _M_t._M_insert_equal_(__position, std::move(__x)); }
#endif
/**
* @brief A template function that tries to insert a range of elements.
* @param __first Iterator pointing to the start of the range to be
* inserted.
* @param __last Iterator pointing to the end of the range.
*
* Complexity similar to that of the range constructor.
*/
template<typename _InputIterator>
void
insert(_InputIterator __first, _InputIterator __last)
{ _M_t._M_insert_equal(__first, __last); }
#if __cplusplus >= 201103L
/**
* @brief Attempts to insert a list of elements into the %multiset.
* @param __l A std::initializer_list<value_type> of elements
* to be inserted.
*
* Complexity similar to that of the range constructor.
*/
void
insert(initializer_list<value_type> __l)
{ this->insert(__l.begin(), __l.end()); }
#endif
#if __cplusplus >= 201103L
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 130. Associative erase should return an iterator.
/**
* @brief Erases an element from a %multiset.
* @param __position An iterator pointing to the element to be erased.
* @return An iterator pointing to the element immediately following
* @a position prior to the element being erased. If no such
* element exists, end() is returned.
*
* This function erases an element, pointed to by the given iterator,
* from a %multiset. Note that this function only erases the element,
* and that if the element is itself a pointer, the pointed-to memory is
* not touched in any way. Managing the pointer is the user's
* responsibility.
*/
iterator
erase(const_iterator __position)
{ return _M_t.erase(__position); }
#else
/**
* @brief Erases an element from a %multiset.
* @param __position An iterator pointing to the element to be erased.
*
* This function erases an element, pointed to by the given iterator,
* from a %multiset. Note that this function only erases the element,
* and that if the element is itself a pointer, the pointed-to memory is
* not touched in any way. Managing the pointer is the user's
* responsibility.
*/
void
erase(iterator __position)
{ _M_t.erase(__position); }
#endif
/**
* @brief Erases elements according to the provided key.
* @param __x Key of element to be erased.
* @return The number of elements erased.
*
* This function erases all elements located by the given key from a
* %multiset.
* Note that this function only erases the element, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibility.
*/
size_type
erase(const key_type& __x)
{ return _M_t.erase(__x); }
#if __cplusplus >= 201103L
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 130. Associative erase should return an iterator.
/**
* @brief Erases a [first,last) range of elements from a %multiset.
* @param __first Iterator pointing to the start of the range to be
* erased.
* @param __last Iterator pointing to the end of the range to
* be erased.
* @return The iterator @a last.
*
* This function erases a sequence of elements from a %multiset.
* Note that this function only erases the elements, and that if
* the elements themselves are pointers, the pointed-to memory is not
* touched in any way. Managing the pointer is the user's
* responsibility.
*/
iterator
erase(const_iterator __first, const_iterator __last)
{ return _M_t.erase(__first, __last); }
#else
/**
* @brief Erases a [first,last) range of elements from a %multiset.
* @param first Iterator pointing to the start of the range to be
* erased.
* @param last Iterator pointing to the end of the range to be erased.
*
* This function erases a sequence of elements from a %multiset.
* Note that this function only erases the elements, and that if
* the elements themselves are pointers, the pointed-to memory is not
* touched in any way. Managing the pointer is the user's
* responsibility.
*/
void
erase(iterator __first, iterator __last)
{ _M_t.erase(__first, __last); }
#endif
/**
* Erases all elements in a %multiset. Note that this function only
* erases the elements, and that if the elements themselves are pointers,
* the pointed-to memory is not touched in any way. Managing the pointer
* is the user's responsibility.
*/
void
clear() _GLIBCXX_NOEXCEPT
{ _M_t.clear(); }
// multiset operations:
/**
* @brief Finds the number of elements with given key.
* @param __x Key of elements to be located.
* @return Number of elements with specified key.
*/
size_type
count(const key_type& __x) const
{ return _M_t.count(__x); }
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 214. set::find() missing const overload
//@{
/**
* @brief Tries to locate an element in a %set.
* @param __x Element to be located.
* @return Iterator pointing to sought-after element, or end() if not
* found.
*
* This function takes a key and tries to locate the element with which
* the key matches. If successful the function returns an iterator
* pointing to the sought after element. If unsuccessful it returns the
* past-the-end ( @c end() ) iterator.
*/
iterator
find(const key_type& __x)
{ return _M_t.find(__x); }
const_iterator
find(const key_type& __x) const
{ return _M_t.find(__x); }
//@}
//@{
/**
* @brief Finds the beginning of a subsequence matching given key.
* @param __x Key to be located.
* @return Iterator pointing to first element equal to or greater
* than key, or end().
*
* This function returns the first element of a subsequence of elements
* that matches the given key. If unsuccessful it returns an iterator
* pointing to the first element that has a greater value than given key
* or end() if no such element exists.
*/
iterator
lower_bound(const key_type& __x)
{ return _M_t.lower_bound(__x); }
const_iterator
lower_bound(const key_type& __x) const
{ return _M_t.lower_bound(__x); }
//@}
//@{
/**
* @brief Finds the end of a subsequence matching given key.
* @param __x Key to be located.
* @return Iterator pointing to the first element
* greater than key, or end().
*/
iterator
upper_bound(const key_type& __x)
{ return _M_t.upper_bound(__x); }
const_iterator
upper_bound(const key_type& __x) const
{ return _M_t.upper_bound(__x); }
//@}
//@{
/**
* @brief Finds a subsequence matching given key.
* @param __x Key to be located.
* @return Pair of iterators that possibly points to the subsequence
* matching given key.
*
* This function is equivalent to
* @code
* std::make_pair(c.lower_bound(val),
* c.upper_bound(val))
* @endcode
* (but is faster than making the calls separately).
*
* This function probably only makes sense for multisets.
*/
std::pair<iterator, iterator>
equal_range(const key_type& __x)
{ return _M_t.equal_range(__x); }
std::pair<const_iterator, const_iterator>
equal_range(const key_type& __x) const
{ return _M_t.equal_range(__x); }
//@}
template<typename _K1, typename _C1, typename _A1>
friend bool
operator==(const multiset<_K1, _C1, _A1>&,
const multiset<_K1, _C1, _A1>&);
template<typename _K1, typename _C1, typename _A1>
friend bool
operator< (const multiset<_K1, _C1, _A1>&,
const multiset<_K1, _C1, _A1>&);
};
/**
* @brief Multiset equality comparison.
* @param __x A %multiset.
* @param __y A %multiset of the same type as @a __x.
* @return True iff the size and elements of the multisets are equal.
*
* This is an equivalence relation. It is linear in the size of the
* multisets.
* Multisets are considered equivalent if their sizes are equal, and if
* corresponding elements compare equal.
*/
template<typename _Key, typename _Compare, typename _Alloc>
inline bool
operator==(const multiset<_Key, _Compare, _Alloc>& __x,
const multiset<_Key, _Compare, _Alloc>& __y)
{ return __x._M_t == __y._M_t; }
/**
* @brief Multiset ordering relation.
* @param __x A %multiset.
* @param __y A %multiset of the same type as @a __x.
* @return True iff @a __x is lexicographically less than @a __y.
*
* This is a total ordering relation. It is linear in the size of the
* maps. The elements must be comparable with @c <.
*
* See std::lexicographical_compare() for how the determination is made.
*/
template<typename _Key, typename _Compare, typename _Alloc>
inline bool
operator<(const multiset<_Key, _Compare, _Alloc>& __x,
const multiset<_Key, _Compare, _Alloc>& __y)
{ return __x._M_t < __y._M_t; }
/// Returns !(x == y).
template<typename _Key, typename _Compare, typename _Alloc>
inline bool
operator!=(const multiset<_Key, _Compare, _Alloc>& __x,
const multiset<_Key, _Compare, _Alloc>& __y)
{ return !(__x == __y); }
/// Returns y < x.
template<typename _Key, typename _Compare, typename _Alloc>
inline bool
operator>(const multiset<_Key,_Compare,_Alloc>& __x,
const multiset<_Key,_Compare,_Alloc>& __y)
{ return __y < __x; }
/// Returns !(y < x)
template<typename _Key, typename _Compare, typename _Alloc>
inline bool
operator<=(const multiset<_Key, _Compare, _Alloc>& __x,
const multiset<_Key, _Compare, _Alloc>& __y)
{ return !(__y < __x); }
/// Returns !(x < y)
template<typename _Key, typename _Compare, typename _Alloc>
inline bool
operator>=(const multiset<_Key, _Compare, _Alloc>& __x,
const multiset<_Key, _Compare, _Alloc>& __y)
{ return !(__x < __y); }
/// See std::multiset::swap().
template<typename _Key, typename _Compare, typename _Alloc>
inline void
swap(multiset<_Key, _Compare, _Alloc>& __x,
multiset<_Key, _Compare, _Alloc>& __y)
{ __x.swap(__y); }
_GLIBCXX_END_NAMESPACE_CONTAINER
} // namespace std
#endif /* _STL_MULTISET_H */