std::multimap< _Key, _Tp, _Compare, _Alloc > Class Template Reference
Containers » Associative

## Public Types

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::iterator | iterator
typedef _Compare | key_compare
typedef _Key | key_type
typedef _Tp | mapped_type
typedef _Alloc_traits::pointer | pointer
typedef _Alloc_traits::reference | reference
typedef _Rep_type::reverse_iterator | reverse_iterator
typedef _Rep_type::size_type | size_type
typedef std::pair< const _Key, _Tp > | value_type

## Public Member Functions

| multimap ()=default
| multimap (const _Compare &__comp, const allocator_type &__a=allocator_type())
| multimap (const multimap &)=default
| multimap (multimap &&)=default
| multimap (initializer_list< value_type > __l, const _Compare &__comp=_Compare(), const allocator_type &__a=allocator_type())
| multimap (const allocator_type &__a)
| multimap (const multimap &__m, const allocator_type &__a)
| multimap (multimap &&__m, const allocator_type &__a) noexcept(is_nothrow_copy_constructible< _Compare >::value &&_Alloc_traits::_S_always_equal())
| multimap (initializer_list< value_type > __l, const allocator_type &__a)
template<typename _InputIterator >
| multimap (_InputIterator __first, _InputIterator __last, const allocator_type &__a)
template<typename _InputIterator >
| multimap (_InputIterator __first, _InputIterator __last)
template<typename _InputIterator >
| multimap (_InputIterator __first, _InputIterator __last, const _Compare &__comp, const allocator_type &__a=allocator_type())
| ~multimap ()=default
iterator | begin () noexcept
const_iterator | begin () const noexcept
const_iterator | cbegin () const noexcept
const_iterator | cend () const noexcept
void | clear () noexcept
const_reverse_iterator | crbegin () const noexcept
const_reverse_iterator | crend () const noexcept
template<typename... _Args>
iterator | emplace (_Args &&... __args)
template<typename... _Args>
iterator | emplace_hint (const_iterator __pos, _Args &&... __args)
bool | empty () const noexcept
iterator | end () noexcept
const_iterator | end () const noexcept
size_type | erase (const key_type &__x)
iterator | erase (const_iterator __first, const_iterator __last)
allocator_type | get_allocator () const noexcept
template<typename _InputIterator >
void | insert (_InputIterator __first, _InputIterator __last)
void | insert (initializer_list< value_type > __l)
key_compare | key_comp () const
size_type | max_size () const noexcept
multimap & | operator= (const multimap &)=default
multimap & | operator= (multimap &&)=default
multimap & | operator= (initializer_list< value_type > __l)
reverse_iterator | rbegin () noexcept
const_reverse_iterator | rbegin () const noexcept
reverse_iterator | rend () noexcept
const_reverse_iterator | rend () const noexcept
size_type | size () const noexcept
void | swap (multimap &__x) noexcept(/*conditional */)
value_compare | value_comp () const
iterator | insert (const value_type &__x)
iterator | insert (value_type &&__x)
template<typename _Pair , typename = typename std::enable_if<std::is_constructible<value_type, _Pair&&>::value>::type>
iterator | insert (_Pair &&__x)
iterator | insert (const_iterator __position, const value_type &__x)
iterator | insert (const_iterator __position, value_type &&__x)
template<typename _Pair , typename = typename std::enable_if<std::is_constructible<value_type, _Pair&&>::value>::type>
iterator | insert (const_iterator __position, _Pair &&__x)
iterator | erase (const_iterator __position)
_GLIBCXX_ABI_TAG_CXX11 iterator | erase (iterator __position)
iterator | find (const key_type &__x)
template<typename _Kt >
auto | find (const _Kt &__x) -> decltype(_M_t._M_find_tr(__x))
const_iterator | find (const key_type &__x) const
template<typename _Kt >
auto | find (const _Kt &__x) const -> decltype(_M_t._M_find_tr(__x))
size_type | count (const key_type &__x) const
template<typename _Kt >
auto | count (const _Kt &__x) const -> decltype(_M_t._M_count_tr(__x))
iterator | lower_bound (const key_type &__x)
template<typename _Kt >
auto | lower_bound (const _Kt &__x) -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
const_iterator | lower_bound (const key_type &__x) const
template<typename _Kt >
auto | lower_bound (const _Kt &__x) const -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
iterator | upper_bound (const key_type &__x)
template<typename _Kt >
auto | upper_bound (const _Kt &__x) -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
const_iterator | upper_bound (const key_type &__x) const
template<typename _Kt >
auto | upper_bound (const _Kt &__x) const -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
std::pair< iterator, iterator > | equal_range (const key_type &__x)
template<typename _Kt >
auto | equal_range (const _Kt &__x) -> decltype(pair< iterator, iterator >(_M_t._M_equal_range_tr(__x)))
std::pair< const_iterator, const_iterator > | equal_range (const key_type &__x) const
template<typename _Kt >
auto | equal_range (const _Kt &__x) const -> decltype(pair< const_iterator, const_iterator >(_M_t._M_equal_range_tr(__x)))

## Friends

template<typename _K1 , typename _T1 , typename _C1 , typename _A1 >
bool | operator< (const multimap< _K1, _T1, _C1, _A1 > &, const multimap< _K1, _T1, _C1, _A1 > &)
template<typename _K1 , typename _T1 , typename _C1 , typename _A1 >
bool | operator== (const multimap< _K1, _T1, _C1, _A1 > &, const multimap< _K1, _T1, _C1, _A1 > &)

## Detailed Description

### template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
class std::multimap< _Key, _Tp, _Compare, _Alloc >

A standard container made up of (key,value) pairs, which can be retrieved based on a key, in logarithmic time.

Template Parameters

  _Key | Type of key objects.
  _Tp | Type of mapped objects.
  _Compare | Comparison function object type, defaults to less<_Key>.
  _Alloc | Allocator type, defaults to allocator<pair<const _Key, _Tp>.

Meets the requirements of a container, a reversible container, and an associative container (using equivalent keys). For a `multimap<Key,T>` the key_type is Key, the mapped_type is T, and the value_type is std::pair<const Key,T>.

Multimaps support bidirectional iterators.

The private tree data is declared exactly the same way for map and multimap; the distinction is made entirely in how the tree functions are called (*_unique versus *_equal, same as the standard).

Definition at line 72 of file stl_map.h.

## Constructor & Destructor Documentation

## multimap() [1/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( |  | ) |

default

Default constructor creates no elements.

Referenced by std::multimap< _Key, _Tp, _Compare, _Alloc >::equal_range(), and std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap().

## multimap() [2/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | const _Compare & | __comp,
|  | const allocator_type & | __a = `allocator_type()`
| ) |  |

inline explicit

Creates a multimap with no elements.

Parameters

  __comp | A comparison object.
  __a | An allocator object.

Definition at line 189 of file stl_multimap.h.

References std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap().

## multimap() [3/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | const multimap< _Key, _Tp, _Compare, _Alloc > & |  | ) |

default

Multimap copy constructor.

Whether the allocator is copied depends on the allocator traits.

## multimap() [4/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | multimap< _Key, _Tp, _Compare, _Alloc > && |  | ) |

default

Multimap move constructor.

The newly-created multimap contains the exact contents of the moved instance. The moved instance is a valid, but unspecified multimap.

## multimap() [5/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | initializer_list< value_type > | __l,
|  | const _Compare & | __comp = `_Compare()`,
|  | const allocator_type & | __a = `allocator_type()`
| ) |  |

inline

Builds a multimap from an initializer_list.

Parameters

  __l | An initializer_list.
  __comp | A comparison functor.
  __a | An allocator object.

Create a multimap consisting of copies of the elements from the initializer_list. This is linear in N if the list is already sorted, and NlogN otherwise (where N is __l.size()).

Definition at line 223 of file stl_multimap.h.

## multimap() [6/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | const allocator_type & | __a | ) |

inline explicit

Allocator-extended default constructor.

Definition at line 231 of file stl_multimap.h.

## multimap() [7/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | const multimap< _Key, _Tp, _Compare, _Alloc > & | __m,
|  | const allocator_type & | __a
| ) |  |

inline

Allocator-extended copy constructor.

Definition at line 235 of file stl_multimap.h.

## multimap() [8/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | multimap< _Key, _Tp, _Compare, _Alloc > && | __m,
|  | const allocator_type & | __a
| ) |  |

inline noexcept

Allocator-extended move constructor.

Definition at line 239 of file stl_multimap.h.

## multimap() [9/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | initializer_list< value_type > | __l,
|  | const allocator_type & | __a
| ) |  |

inline

Allocator-extended initialier-list constructor.

Definition at line 245 of file stl_multimap.h.

## multimap() [10/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _InputIterator >

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | _InputIterator | __first,
|  | _InputIterator | __last,
|  | const allocator_type & | __a
| ) |  |

inline

Allocator-extended range constructor.

Definition at line 251 of file stl_multimap.h.

## multimap() [11/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _InputIterator >

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | _InputIterator | __first,
|  | _InputIterator | __last
| ) |  |

inline

Builds a multimap from a range.

Parameters

  __first | An input iterator.
  __last | An input iterator.

Create a multimap 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)).

Definition at line 267 of file stl_multimap.h.

## multimap() [12/12]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _InputIterator >

std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap | ( | _InputIterator | __first,
|  | _InputIterator | __last,
|  | const _Compare & | __comp,
|  | const allocator_type & | __a = `allocator_type()`
| ) |  |

inline

Builds a multimap from a range.

Parameters

  __first | An input iterator.
  __last | An input iterator.
  __comp | A comparison functor.
  __a | An allocator object.

Create a multimap 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)).

Definition at line 283 of file stl_multimap.h.

References std::multimap< _Key, _Tp, _Compare, _Alloc >::operator=(), and std::multimap< _Key, _Tp, _Compare, _Alloc >::~multimap().

## ~multimap()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::multimap< _Key, _Tp, _Compare, _Alloc >::~multimap | ( |  | ) |

default

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.

Referenced by std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap().

## Member Function Documentation

## begin() [1/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::begin | ( |  | ) |

inline noexcept

Returns a read/write iterator that points to the first pair in the multimap. Iteration is done in ascending order according to the keys.

Definition at line 349 of file stl_multimap.h.

## begin() [2/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::begin | ( |  | ) | const

inline noexcept

Returns a read-only (constant) iterator that points to the first pair in the multimap. Iteration is done in ascending order according to the keys.

Definition at line 358 of file stl_multimap.h.

## cbegin()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::cbegin | ( |  | ) | const

inline noexcept

Returns a read-only (constant) iterator that points to the first pair in the multimap. Iteration is done in ascending order according to the keys.

Definition at line 422 of file stl_multimap.h.

## cend()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::cend | ( |  | ) | const

inline noexcept

Returns a read-only (constant) iterator that points one past the last pair in the multimap. Iteration is done in ascending order according to the keys.

Definition at line 431 of file stl_multimap.h.

## clear()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

void std::multimap< _Key, _Tp, _Compare, _Alloc >::clear | ( |  | ) |

inline noexcept

Erases all elements in a multimap. 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.

Definition at line 808 of file stl_multimap.h.

## count() [1/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

size_type std::multimap< _Key, _Tp, _Compare, _Alloc >::count | ( | const key_type & | __x | ) | const

inline

Finds the number of elements with given key.

Parameters

  __x | Key of (key, value) pairs to be located.

Returns
  Number of elements with specified key.

Definition at line 885 of file stl_multimap.h.

## count() [2/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::count | ( | const _Kt & | __x | ) | const -> decltype(_M_t._M_count_tr(__x))

inline

Finds the number of elements with given key.

Parameters

  __x | Key of (key, value) pairs to be located.

Returns
  Number of elements with specified key.

Definition at line 891 of file stl_multimap.h.

## crbegin()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_reverse_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::crbegin | ( |  | ) | const

inline noexcept

Returns a read-only (constant) reverse iterator that points to the last pair in the multimap. Iteration is done in descending order according to the keys.

Definition at line 440 of file stl_multimap.h.

## crend()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_reverse_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::crend | ( |  | ) | const

inline noexcept

Returns a read-only (constant) reverse iterator that points to one before the first pair in the multimap. Iteration is done in descending order according to the keys.

Definition at line 449 of file stl_multimap.h.

## emplace()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename... _Args>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::emplace | ( | _Args &&... | __args | ) |

inline

Build and insert a std::pair into the multimap.

Parameters

  __args | Arguments used to generate a new pair instance (see std::piecewise_contruct for passing arguments to each part of the pair constructor).

Returns
  An iterator that points to the inserted (key,value) pair.

This function builds and inserts a (key, value) pair into the multimap. Contrary to a std::map the multimap does not rely on unique keys and thus multiple pairs with the same key can be inserted.

Insertion requires logarithmic time.

Definition at line 489 of file stl_multimap.h.

## emplace_hint()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename... _Args>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::emplace_hint | ( | const_iterator | __pos,
|  | _Args &&... | __args
| ) |  |

inline

Builds and inserts a std::pair into the multimap.

Parameters

  __pos | An iterator that serves as a hint as to where the pair should be inserted.
  __args | Arguments used to generate a new pair instance (see std::piecewise_contruct for passing arguments to each part of the pair constructor).

Returns
  An iterator that points to the inserted (key,value) pair.

This function inserts a (key, value) pair into the multimap. Contrary to a std::map the multimap does not rely on unique keys and thus multiple pairs with the same key 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.

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

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

Definition at line 516 of file stl_multimap.h.

## empty()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

bool std::multimap< _Key, _Tp, _Compare, _Alloc >::empty | ( |  | ) | const

inline noexcept

Returns true if the multimap is empty.

Definition at line 456 of file stl_multimap.h.

## end() [1/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::end | ( |  | ) |

inline noexcept

Returns a read/write iterator that points one past the last pair in the multimap. Iteration is done in ascending order according to the keys.

Definition at line 367 of file stl_multimap.h.

## end() [2/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::end | ( |  | ) | const

inline noexcept

Returns a read-only (constant) iterator that points one past the last pair in the multimap. Iteration is done in ascending order according to the keys.

Definition at line 376 of file stl_multimap.h.

## equal_range() [1/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::pair<iterator, iterator> std::multimap< _Key, _Tp, _Compare, _Alloc >::equal_range | ( | const key_type & | __x | ) |

inline

Finds a subsequence matching given key.

Parameters

  __x | Key of (key, value) pairs to be located.

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).

Definition at line 1001 of file stl_multimap.h.

## equal_range() [2/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::equal_range | ( | const _Kt & | __x | ) | -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))

inline

Finds a subsequence matching given key.

Parameters

  __x | Key of (key, value) pairs to be located.

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).

Definition at line 1007 of file stl_multimap.h.

## equal_range() [3/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

std::pair<const_iterator, const_iterator> std::multimap< _Key, _Tp, _Compare, _Alloc >::equal_range | ( | const key_type & | __x | ) | const

inline

Finds a subsequence matching given key.

Parameters

  __x | Key of (key, value) pairs to be located.

Returns
  Pair of read-only (constant) 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).

Definition at line 1028 of file stl_multimap.h.

## equal_range() [4/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::equal_range | ( | const _Kt & | __x | ) | const -> decltype(pair<const_iterator, const_iterator>( _M_t._M_equal_range_tr(__x)))

inline

Finds a subsequence matching given key.

Parameters

  __x | Key of (key, value) pairs to be located.

Returns
  Pair of read-only (constant) 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).

Definition at line 1034 of file stl_multimap.h.

References std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap().

## erase() [1/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::erase | ( | const_iterator | __position | ) |

inline

Erases an element from a multimap.

Parameters

  __position | An iterator pointing to the element to be erased.

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 multimap. 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.

Definition at line 702 of file stl_multimap.h.

Referenced by std::multimap< _Key, _Tp, _Compare, _Alloc >::erase().

## erase() [2/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

_GLIBCXX_ABI_TAG_CXX11 iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::erase | ( | iterator | __position | ) |

inline

Erases an element from a multimap.

Parameters

  __position | An iterator pointing to the element to be erased.

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 multimap. 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.

Definition at line 708 of file stl_multimap.h.

References std::multimap< _Key, _Tp, _Compare, _Alloc >::erase().

## erase() [3/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

size_type std::multimap< _Key, _Tp, _Compare, _Alloc >::erase | ( | const key_type & | __x | ) |

inline

Erases elements according to the provided key.

Parameters

  __x | Key of element to be erased.

Returns
  The number of elements erased.

This function erases all elements located by the given key from a multimap. 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.

Definition at line 739 of file stl_multimap.h.

## erase() [4/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::erase | ( | const_iterator | __first,
|  | const_iterator | __last
| ) |  |

inline

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

Parameters

  __first | Iterator pointing to the start of the range to be erased.
  __last | Iterator pointing to the end of the range to be erased .

Returns
  The iterator __last.

This function erases a sequence of elements from a multimap. 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.

Definition at line 760 of file stl_multimap.h.

References std::multimap< _Key, _Tp, _Compare, _Alloc >::erase().

## find() [1/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::find | ( | const key_type & | __x | ) |

inline

Tries to locate an element in a multimap.

Parameters

  __x | Key of (key, value) pair to be located.

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 pair. If unsuccessful it returns the past-the-end ( `end()` ) iterator.

Definition at line 843 of file stl_multimap.h.

## find() [2/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::find | ( | const _Kt & | __x | ) | -> decltype(_M_t._M_find_tr(__x))

inline

Tries to locate an element in a multimap.

Parameters

  __x | Key of (key, value) pair to be located.

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 pair. If unsuccessful it returns the past-the-end ( `end()` ) iterator.

Definition at line 849 of file stl_multimap.h.

## find() [3/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::find | ( | const key_type & | __x | ) | const

inline

Tries to locate an element in a multimap.

Parameters

  __x | Key of (key, value) pair to be located.

Returns
  Read-only (constant) 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 a constant iterator pointing to the sought after pair. If unsuccessful it returns the past-the-end ( `end()` ) iterator.

Definition at line 867 of file stl_multimap.h.

## find() [4/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::find | ( | const _Kt & | __x | ) | const -> decltype(_M_t._M_find_tr(__x))

inline

Tries to locate an element in a multimap.

Parameters

  __x | Key of (key, value) pair to be located.

Returns
  Read-only (constant) 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 a constant iterator pointing to the sought after pair. If unsuccessful it returns the past-the-end ( `end()` ) iterator.

Definition at line 873 of file stl_multimap.h.

## get_allocator()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

allocator_type std::multimap< _Key, _Tp, _Compare, _Alloc >::get_allocator | ( |  | ) | const

inline noexcept

Get a copy of the memory allocation object.

Definition at line 339 of file stl_multimap.h.

## insert() [1/8]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::insert | ( | const value_type & | __x | ) |

inline

Inserts a std::pair into the multimap.

Parameters

  __x | Pair to be inserted (see std::make_pair for easy creation of pairs).

Returns
  An iterator that points to the inserted (key,value) pair.

This function inserts a (key, value) pair into the multimap. Contrary to a std::map the multimap does not rely on unique keys and thus multiple pairs with the same key can be inserted.

Insertion requires logarithmic time.

Definition at line 537 of file stl_multimap.h.

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

## insert() [2/8]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::insert | ( | value_type && | __x | ) |

inline

Inserts a std::pair into the multimap.

Parameters

  __x | Pair to be inserted (see std::make_pair for easy creation of pairs).

Returns
  An iterator that points to the inserted (key,value) pair.

This function inserts a (key, value) pair into the multimap. Contrary to a std::map the multimap does not rely on unique keys and thus multiple pairs with the same key can be inserted.

Insertion requires logarithmic time.

Definition at line 544 of file stl_multimap.h.

## insert() [3/8]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Pair , typename = typename std::enable_if<std::is_constructible<value_type, _Pair&&>::value>::type>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::insert | ( | _Pair && | __x | ) |

inline

Inserts a std::pair into the multimap.

Parameters

  __x | Pair to be inserted (see std::make_pair for easy creation of pairs).

Returns
  An iterator that points to the inserted (key,value) pair.

This function inserts a (key, value) pair into the multimap. Contrary to a std::map the multimap does not rely on unique keys and thus multiple pairs with the same key can be inserted.

Insertion requires logarithmic time.

Definition at line 551 of file stl_multimap.h.

## insert() [4/8]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::insert | ( | const_iterator | __position,
|  | const value_type & | __x
| ) |  |

inline

Inserts a std::pair into the multimap.

Parameters

  __position | An iterator that serves as a hint as to where the pair should be inserted.
  __x | Pair to be inserted (see std::make_pair for easy creation of pairs).

Returns
  An iterator that points to the inserted (key,value) pair.

This function inserts a (key, value) pair into the multimap. Contrary to a std::map the multimap does not rely on unique keys and thus multiple pairs with the same key 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.

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

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

Definition at line 579 of file stl_multimap.h.

## insert() [5/8]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::insert | ( | const_iterator | __position,
|  | value_type && | __x
| ) |  |

inline

Inserts a std::pair into the multimap.

Parameters

  __position | An iterator that serves as a hint as to where the pair should be inserted.
  __x | Pair to be inserted (see std::make_pair for easy creation of pairs).

Returns
  An iterator that points to the inserted (key,value) pair.

This function inserts a (key, value) pair into the multimap. Contrary to a std::map the multimap does not rely on unique keys and thus multiple pairs with the same key 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.

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

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

Definition at line 589 of file stl_multimap.h.

## insert() [6/8]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Pair , typename = typename std::enable_if<std::is_constructible<value_type, _Pair&&>::value>::type>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::insert | ( | const_iterator | __position,
|  | _Pair && | __x
| ) |  |

inline

Inserts a std::pair into the multimap.

Parameters

  __position | An iterator that serves as a hint as to where the pair should be inserted.
  __x | Pair to be inserted (see std::make_pair for easy creation of pairs).

Returns
  An iterator that points to the inserted (key,value) pair.

This function inserts a (key, value) pair into the multimap. Contrary to a std::map the multimap does not rely on unique keys and thus multiple pairs with the same key 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.

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

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

Definition at line 596 of file stl_multimap.h.

## insert() [7/8]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _InputIterator >

void std::multimap< _Key, _Tp, _Compare, _Alloc >::insert | ( | _InputIterator | __first,
|  | _InputIterator | __last
| ) |  |

inline

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

Parameters

  __first | Iterator pointing to the start of the range to be inserted.
  __last | Iterator pointing to the end of the range.

Complexity similar to that of the range constructor.

Definition at line 613 of file stl_multimap.h.

## insert() [8/8]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

void std::multimap< _Key, _Tp, _Compare, _Alloc >::insert | ( | initializer_list< value_type > | __l | ) |

inline

Attempts to insert a list of std::pairs into the multimap.

Parameters

  __l | A std::initializer_list<value_type> of pairs to be inserted.

Complexity similar to that of the range constructor.

Definition at line 625 of file stl_multimap.h.

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

## key_comp()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

key_compare std::multimap< _Key, _Tp, _Compare, _Alloc >::key_comp | ( |  | ) | const

inline

Returns the key comparison object out of which the multimap was constructed.

Definition at line 817 of file stl_multimap.h.

## lower_bound() [1/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::lower_bound | ( | const key_type & | __x | ) |

inline

Finds the beginning of a subsequence matching given key.

Parameters

  __x | Key of (key, value) pair to be located.

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.

Definition at line 909 of file stl_multimap.h.

## lower_bound() [2/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::lower_bound | ( | const _Kt & | __x | ) | -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))

inline

Finds the beginning of a subsequence matching given key.

Parameters

  __x | Key of (key, value) pair to be located.

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.

Definition at line 915 of file stl_multimap.h.

## lower_bound() [3/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::lower_bound | ( | const key_type & | __x | ) | const

inline

Finds the beginning of a subsequence matching given key.

Parameters

  __x | Key of (key, value) pair to be located.

Returns
  Read-only (constant) 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 the iterator will point to the next greatest element or, if no such greater element exists, to end().

Definition at line 934 of file stl_multimap.h.

## lower_bound() [4/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::lower_bound | ( | const _Kt & | __x | ) | const -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))

inline

Finds the beginning of a subsequence matching given key.

Parameters

  __x | Key of (key, value) pair to be located.

Returns
  Read-only (constant) 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 the iterator will point to the next greatest element or, if no such greater element exists, to end().

Definition at line 940 of file stl_multimap.h.

## max_size()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

size_type std::multimap< _Key, _Tp, _Compare, _Alloc >::max_size | ( |  | ) | const

inline noexcept

Returns the maximum size of the multimap.

Definition at line 466 of file stl_multimap.h.

## operator=() [1/3]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

multimap& std::multimap< _Key, _Tp, _Compare, _Alloc >::operator= | ( | const multimap< _Key, _Tp, _Compare, _Alloc > & |  | ) |

default

Multimap assignment operator.

Whether the allocator is copied depends on the allocator traits.

Referenced by std::multimap< _Key, _Tp, _Compare, _Alloc >::multimap().

## operator=() [2/3]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

multimap& std::multimap< _Key, _Tp, _Compare, _Alloc >::operator= | ( | multimap< _Key, _Tp, _Compare, _Alloc > && |  | ) |

default

Move assignment operator.

## operator=() [3/3]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

multimap& std::multimap< _Key, _Tp, _Compare, _Alloc >::operator= | ( | initializer_list< value_type > | __l | ) |

inline

Multimap list assignment operator.

Parameters

  __l | An initializer_list.

This function fills a multimap with copies of the elements in the initializer list __l.

Note that the assignment completely changes the multimap and that the resulting multimap's size is the same as the number of elements assigned.

Definition at line 330 of file stl_multimap.h.

## rbegin() [1/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

reverse_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::rbegin | ( |  | ) |

inline noexcept

Returns a read/write reverse iterator that points to the last pair in the multimap. Iteration is done in descending order according to the keys.

Definition at line 385 of file stl_multimap.h.

## rbegin() [2/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_reverse_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::rbegin | ( |  | ) | const

inline noexcept

Returns a read-only (constant) reverse iterator that points to the last pair in the multimap. Iteration is done in descending order according to the keys.

Definition at line 394 of file stl_multimap.h.

## rend() [1/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

reverse_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::rend | ( |  | ) |

inline noexcept

Returns a read/write reverse iterator that points to one before the first pair in the multimap. Iteration is done in descending order according to the keys.

Definition at line 403 of file stl_multimap.h.

## rend() [2/2]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_reverse_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::rend | ( |  | ) | const

inline noexcept

Returns a read-only (constant) reverse iterator that points to one before the first pair in the multimap. Iteration is done in descending order according to the keys.

Definition at line 412 of file stl_multimap.h.

## size()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

size_type std::multimap< _Key, _Tp, _Compare, _Alloc >::size | ( |  | ) | const

inline noexcept

Returns the size of the multimap.

Definition at line 461 of file stl_multimap.h.

## swap()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

void std::multimap< _Key, _Tp, _Compare, _Alloc >::swap | ( | multimap< _Key, _Tp, _Compare, _Alloc > & | __x | ) |

inline noexcept

Swaps data with another multimap.

Parameters

  __x | A multimap of the same element and allocator types.

This exchanges the elements between two multimaps 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(m1,m2) will feed to this function.

Whether the allocators are swapped depends on the allocator traits.

Definition at line 797 of file stl_multimap.h.

## upper_bound() [1/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::upper_bound | ( | const key_type & | __x | ) |

inline

Finds the end of a subsequence matching given key.

Parameters

  __x | Key of (key, value) pair to be located.

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

Definition at line 954 of file stl_multimap.h.

## upper_bound() [2/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::upper_bound | ( | const _Kt & | __x | ) | -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))

inline

Finds the end of a subsequence matching given key.

Parameters

  __x | Key of (key, value) pair to be located.

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

Definition at line 960 of file stl_multimap.h.

## upper_bound() [3/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

const_iterator std::multimap< _Key, _Tp, _Compare, _Alloc >::upper_bound | ( | const key_type & | __x | ) | const

inline

Finds the end of a subsequence matching given key.

Parameters

  __x | Key of (key, value) pair to be located.

Returns
  Read-only (constant) iterator pointing to first iterator greater than key, or end().

Definition at line 974 of file stl_multimap.h.

## upper_bound() [4/4]

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>
template<typename _Kt >

auto std::multimap< _Key, _Tp, _Compare, _Alloc >::upper_bound | ( | const _Kt & | __x | ) | const -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))

inline

Finds the end of a subsequence matching given key.

Parameters

  __x | Key of (key, value) pair to be located.

Returns
  Read-only (constant) iterator pointing to first iterator greater than key, or end().

Definition at line 980 of file stl_multimap.h.

## value_comp()

template<typename _Key, typename _Tp, typename _Compare = std::less<_Key>, typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >>

value_compare std::multimap< _Key, _Tp, _Compare, _Alloc >::value_comp | ( |  | ) | const

inline

Returns a value comparison object, built from the key comparison object out of which the multimap was constructed.

Definition at line 825 of file stl_multimap.h.

The documentation for this class was generated from the following files:

- stl_map.h
- stl_multimap.h