std::multiset - Man Page

typedef _Alloc allocator_type
typedef _Rep_type::const_iterator const_iterator
typedef _Alloc_traits::const_pointer const_pointer
typedef _Alloc_traits::const_reference const_reference
typedef _Rep_type::const_reverse_iterator const_reverse_iterator
typedef _Rep_type::difference_type difference_type
typedef _Rep_type::const_iterator iterator
typedef _Compare key_compare
typedef _Key key_type
using node_type
typedef _Alloc_traits::pointer pointer
typedef _Alloc_traits::reference reference
typedef _Rep_type::const_reverse_iterator reverse_iterator
typedef _Rep_type::size_type size_type
typedef _Compare value_compare
typedef _Key value_type

multiset ()=default
Default constructor creates no elements.
template<typename _InputIterator > multiset (_InputIterator __first, _InputIterator __last)
Builds a multiset from a range.
template<typename _InputIterator > multiset (_InputIterator __first, _InputIterator __last, const _Compare &__comp, const allocator_type &__a=allocator_type())
Builds a multiset from a range.
template<typename _InputIterator > multiset (_InputIterator __first, _InputIterator __last, const allocator_type &__a)
Allocator-extended range constructor.
multiset (const _Compare &__comp, const allocator_type &__a=allocator_type())
Creates a multiset with no elements.
multiset (const allocator_type &__a)
Allocator-extended default constructor.
multiset (const multiset &)=default
Multiset copy constructor.
multiset (const multiset &__m, const __type_identity_t< allocator_type > &__a)
Allocator-extended copy constructor.
multiset (initializer_list< value_type > __l, const _Compare &__comp=_Compare(), const allocator_type &__a=allocator_type())
Builds a multiset from an initializer_list.
multiset (initializer_list< value_type > __l, const allocator_type &__a)
Allocator-extended initialier-list constructor.
multiset (multiset &&)=default
Multiset move constructor.
multiset (multiset &&__m, const __type_identity_t< allocator_type > &__a) noexcept(is_nothrow_copy_constructible< _Compare >::value &&_Alloc_traits::_S_always_equal())
Allocator-extended move constructor.
~multiset ()=default
iterator begin () const noexcept
iterator cbegin () const noexcept
iterator cend () const noexcept
void clear () noexcept
reverse_iterator crbegin () const noexcept
reverse_iterator crend () const noexcept
template<typename... _Args> iterator emplace (_Args &&... __args)
Builds and inserts an element into the multiset.
template<typename... _Args> iterator emplace_hint (const_iterator __pos, _Args &&... __args)
Builds and inserts an element into the multiset.
bool empty () const noexcept
Returns true if the set is empty.
iterator end () const noexcept
size_type erase (const key_type &__x)
Erases elements according to the provided key.
_GLIBCXX_ABI_TAG_CXX11 iterator erase (const_iterator __first, const_iterator __last)
Erases a [first,last) range of elements from a multiset.
_GLIBCXX_ABI_TAG_CXX11 iterator erase (const_iterator __position)
Erases an element from a multiset.
node_type extract (const key_type &__x)
Extract a node.
node_type extract (const_iterator __pos)
Extract a node.
allocator_type get_allocator () const noexcept
Returns the memory allocation object.
template<typename _InputIterator > void insert (_InputIterator __first, _InputIterator __last)
A template function that tries to insert a range of elements.
iterator insert (const value_type &__x)
Inserts an element into the multiset.
iterator insert (const_iterator __hint, node_type &&__nh)
Re-insert an extracted node.
iterator insert (const_iterator __position, const value_type &__x)
Inserts an element into the multiset.
iterator insert (const_iterator __position, value_type &&__x)
void insert (initializer_list< value_type > __l)
Attempts to insert a list of elements into the multiset.
iterator insert (node_type &&__nh)
Re-insert an extracted node.
iterator insert (value_type &&__x)
key_compare key_comp () const
Returns the comparison object.
size_type max_size () const noexcept
Returns the maximum size of the set.
template<typename _Compare1 > void merge (multiset< _Key, _Compare1, _Alloc > &&__source)
template<typename _Compare1 > void merge (multiset< _Key, _Compare1, _Alloc > &__source)
template<typename _Compare1 > void merge (set< _Key, _Compare1, _Alloc > &&__source)
template<typename _Compare1 > void merge (set< _Key, _Compare1, _Alloc > &__source)
multiset & operator= (const multiset &)=default
Multiset assignment operator.
multiset & operator= (initializer_list< value_type > __l)
Multiset list assignment operator.
multiset & operator= (multiset &&)=default
Move assignment operator.
reverse_iterator rbegin () const noexcept
reverse_iterator rend () const noexcept
size_type size () const noexcept
Returns the size of the set.
void swap (multiset &__x) noexcept(/*conditional */)
Swaps data with another multiset.
value_compare value_comp () const
Returns the comparison object.

size_type count (const key_type &__x) const
Finds the number of elements with given key.
template<typename _Kt > auto count (const _Kt &__x) const -> decltype(_M_t._M_count_tr(__x))
Finds the number of elements with given key.

bool contains (const key_type &__x) const
Finds whether an element with the given key exists.
template<typename _Kt > auto contains (const _Kt &__x) const -> decltype(_M_t._M_find_tr(__x), void(), true)
Finds whether an element with the given key exists.

iterator find (const key_type &__x)
Tries to locate an element in a set.
const_iterator find (const key_type &__x) const
Tries to locate an element in a set.
template<typename _Kt > auto find (const _Kt &__x) -> decltype(iterator{_M_t._M_find_tr(__x)})
Tries to locate an element in a set.
template<typename _Kt > auto find (const _Kt &__x) const -> decltype(const_iterator{_M_t._M_find_tr(__x)})
Tries to locate an element in a set.

iterator lower_bound (const key_type &__x)
Finds the beginning of a subsequence matching given key.
const_iterator lower_bound (const key_type &__x) const
Finds the beginning of a subsequence matching given key.
template<typename _Kt > auto lower_bound (const _Kt &__x) -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
Finds the beginning of a subsequence matching given key.
template<typename _Kt > auto lower_bound (const _Kt &__x) const -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
Finds the beginning of a subsequence matching given key.

iterator upper_bound (const key_type &__x)
Finds the end of a subsequence matching given key.
const_iterator upper_bound (const key_type &__x) const
Finds the end of a subsequence matching given key.
template<typename _Kt > auto upper_bound (const _Kt &__x) -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
Finds the end of a subsequence matching given key.
template<typename _Kt > auto upper_bound (const _Kt &__x) const -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
Finds the end of a subsequence matching given key.

std::pair< iterator, iterator > equal_range (const key_type &__x)
Finds a subsequence matching given key.
std::pair< const_iterator, const_iterator > equal_range (const key_type &__x) const
Finds a subsequence matching given key.
template<typename _Kt > auto equal_range (const _Kt &__x) -> decltype(pair< iterator, iterator >(_M_t._M_equal_range_tr(__x)))
Finds a subsequence matching given key.
template<typename _Kt > auto equal_range (const _Kt &__x) const -> decltype(pair< iterator, iterator >(_M_t._M_equal_range_tr(__x)))
Finds a subsequence matching given key.

template<typename _K1 , typename _C1 , typename _A1 > bool operator< (const multiset< _K1, _C1, _A1 > &, const multiset< _K1, _C1, _A1 > &)
template<typename _K1 , typename _C1 , typename _A1 > bool operator== (const multiset< _K1, _C1, _A1 > &, const multiset< _K1, _C1, _A1 > &)
template<typename , typename > struct std::_Rb_tree_merge_helper

class std::multiset< _Key, _Compare, _Alloc >"A standard container made up of elements, which can be retrieved in logarithmic time.

Since

C++98

Template Parameters

Meets the requirements of a container, a reversible container, and an associative container (using equivalent keys). For a 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).

Default constructor creates no elements.

Creates a multiset with no elements.

Parameters

Builds a multiset from a range.

Parameters

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)).

Builds a multiset from a range.

Parameters

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)).

Multiset copy constructor. Whether the allocator is copied depends on the allocator traits.

Multiset move constructor. The newly-created multiset contains the exact contents of the moved instance. The moved instance is a valid, but unspecified multiset.

Builds a multiset from an initializer_list.

Parameters

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 __l.size()).

Allocator-extended default constructor.

Allocator-extended copy constructor.

Allocator-extended move constructor.

Allocator-extended initialier-list constructor.

Allocator-extended range constructor.

The dtor only erases the elements, and note 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.

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.

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.

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.

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.

[inline]"

Finds whether an element with the given key exists.

Parameters

Returns

True if there is any element with the specified key.

Finds whether an element with the given key exists.

Parameters

Returns

True if there is any element with the specified key.

[inline]"

Finds the number of elements with given key.

Parameters

Returns

Number of elements with specified key.

Finds the number of elements with given key.

Parameters

Returns

Number of elements with specified key.

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.

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.

Builds and inserts an element into the multiset.

Parameters

Returns

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.

References std::forward().

Builds and inserts an element into the multiset.

Parameters

Returns

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 https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints for more on hinting.

Insertion requires logarithmic time (if the hint is not taken).

References std::forward().

Returns true if the set is empty.

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.

Referenced by std::multiset< _Key, _Compare, _Alloc >::extract().

[inline]"

Finds a subsequence matching given key.

Parameters

Returns

Pair of iterators that possibly points to the subsequence matching given key.

This function is equivalent to

std::make_pair(c.lower_bound(val),
               c.upper_bound(val))

(but is faster than making the calls separately).

This function probably only makes sense for multisets.

[inline]"

Finds a subsequence matching given key.

Parameters

Returns

Pair of iterators that possibly points to the subsequence matching given key.

This function is equivalent to

std::make_pair(c.lower_bound(val),
               c.upper_bound(val))

(but is faster than making the calls separately).

This function probably only makes sense for multisets.

Finds a subsequence matching given key.

Parameters

Returns

Pair of iterators that possibly points to the subsequence matching given key.

This function is equivalent to

std::make_pair(c.lower_bound(val),
               c.upper_bound(val))

(but is faster than making the calls separately).

This function probably only makes sense for multisets.

Finds a subsequence matching given key.

Parameters

Returns

Pair of iterators that possibly points to the subsequence matching given key.

This function is equivalent to

std::make_pair(c.lower_bound(val),
               c.upper_bound(val))

(but is faster than making the calls separately).

This function probably only makes sense for multisets.

Erases elements according to the provided key.

Parameters

Returns

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.

Erases a [first,last) range of elements from a multiset.

Parameters

Returns

The iterator 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.

Erases an element from a multiset.

Parameters

Returns

An iterator pointing to the element immediately following 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.

Extract a node.

Extract a node.

References std::multiset< _Key, _Compare, _Alloc >::end().

[inline]"

Tries to locate an element in a set.

Parameters

Returns

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 ( end() ) iterator.

[inline]"

Tries to locate an element in a set.

Parameters

Returns

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 ( end() ) iterator.

Tries to locate an element in a set.

Parameters

Returns

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 ( end() ) iterator.

Tries to locate an element in a set.

Parameters

Returns

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 ( end() ) iterator.

Returns the memory allocation object.

A template function that tries to insert a range of elements.

Parameters

Complexity similar to that of the range constructor.

Inserts an element into the multiset.

Parameters

Returns

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.

Referenced by std::multiset< _Key, _Compare, _Alloc >::insert().

Re-insert an extracted node.

References std::move().

Inserts an element into the multiset.

Parameters

Returns

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 https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints for more on hinting.

Insertion requires logarithmic time (if the hint is not taken).

Attempts to insert a list of elements into the multiset.

Parameters

Complexity similar to that of the range constructor.

References std::multiset< _Key, _Compare, _Alloc >::insert().

Re-insert an extracted node.

References std::move().

Returns the comparison object.

[inline]"

Finds the beginning of a subsequence matching given key.

Parameters

Returns

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.

[inline]"

Finds the beginning of a subsequence matching given key.

Parameters

Returns

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.

Finds the beginning of a subsequence matching given key.

Parameters

Returns

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.

Finds the beginning of a subsequence matching given key.

Parameters

Returns

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.

Returns the maximum size of the set.

Multiset assignment operator. Whether the allocator is copied depends on the allocator traits.

Multiset list assignment operator.

Parameters

This function fills a multiset with copies of the elements in the initializer list __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.

Move assignment operator.

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.

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.

Returns the size of the set.

Swaps data with another multiset.

Parameters

This exchanges the elements between two multisets in constant time. (It is only swapping a pointer, an integer, and an instance of the 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.

Whether the allocators are swapped depends on the allocator traits.

[inline]"

Finds the end of a subsequence matching given key.

Parameters

Returns

Iterator pointing to the first element greater than key, or end().

[inline]"

Finds the end of a subsequence matching given key.

Parameters

Returns

Iterator pointing to the first element greater than key, or end().

Finds the end of a subsequence matching given key.

Parameters

Returns

Iterator pointing to the first element greater than key, or end().

Finds the end of a subsequence matching given key.

Parameters

Returns

Iterator pointing to the first element greater than key, or end().

Returns the comparison object.