std::multimap< Key, Type, Compare, Alloc > Class Template Reference
[Containers, Associative Containers]

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

#include <stl_multimap.h>

Inheritance diagram for std::multimap< Key, Type, Compare, Alloc >:

[legend]Collaboration diagram for std::multimap< Key, Type, Compare, Alloc >:

[legend]List of all members.

Public Types
typedef Key	key_type
typedef Type	mapped_type
typedef pair< const Key, Type >	value_type
typedef Compare	key_compare
typedef Alloc::pointer	pointer
typedef Alloc::const_pointer	const_pointer
typedef Alloc::reference	reference
typedef Alloc::const_reference	const_reference
typedef Rep_type::allocator_type	allocator_type
typedef Rep_type::iterator	iterator
typedef Rep_type::const_iterator	const_iterator
typedef Rep_type::size_type	size_type
typedef Rep_type::difference_type	difference_type
typedef Rep_type::reverse_iterator	reverse_iterator
typedef Rep_type::const_reverse_iterator	const_reverse_iterator
Public Member Functions
	multimap ()
	Default constructor creates no elements.
	multimap (const Compare &comp, const allocator_type &a=allocator_type())
	Default constructor creates no elements.
	multimap (const multimap &x)
	Multimap copy constructor.
template<typename InputIterator>
	multimap (InputIterator first, InputIterator last)
	Builds a multimap from a range.
template<typename InputIterator>
	multimap (InputIterator first, InputIterator last, const Compare &comp, const allocator_type &a=allocator_type())
	Builds a multimap from a range.
multimap &	operator= (const multimap &x)
	Multimap assignment operator.
allocator_type	get_allocator () const
	Get a copy of the memory allocation object.
iterator	begin ()
const_iterator	begin () const
iterator	end ()
const_iterator	end () const
reverse_iterator	rbegin ()
const_reverse_iterator	rbegin () const
reverse_iterator	rend ()
const_reverse_iterator	rend () const
bool	empty () const
size_type	size () const
size_type	max_size () const
iterator	insert (const value_type &x)
	Inserts a std::pair into the multimap.
iterator	insert (iterator position, const value_type &x)
	Inserts a std::pair into the multimap.
template<typename InputIterator>
void	insert (InputIterator first, InputIterator last)
	A template function that attemps to insert a range of elements.
void	erase (iterator position)
	Erases an element from a multimap.
size_type	erase (const key_type &x)
	Erases elements according to the provided key.
void	erase (iterator first, iterator last)
	Erases a [first,last) range of elements from a multimap.
void	swap (multimap &x)
	Swaps data with another multimap.
void	clear ()
key_compare	key_comp () const
value_compare	value_comp () const
iterator	find (const key_type &x)
	Tries to locate an element in a multimap.
const_iterator	find (const key_type &x) const
	Tries to locate an element in a multimap.
size_type	count (const key_type &x) const
	Finds the number of elements with given key.
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.
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.
pair< iterator, iterator >	equal_range (const key_type &x)
	Finds a subsequence matching given key.
pair< const_iterator, const_iterator >	equal_range (const key_type &x) const
	Finds a subsequence matching given key.
Private Types
typedef Rb_tree< key_type, value_type, Select1st< value_type >, key_compare, Alloc >	Rep_type
Private Attributes
Rep_type	M_t
Classes
class	value_compare

---

Detailed Description

template<typename Key, typename Type, typename Compare, typename Alloc>
class std::multimap< Key, Type, Compare, Alloc >

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

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.

Definition at line 107 of file stl_multimap.h.

---

Constructor & Destructor Documentation

template<typename Key, typename Type, typename Compare, typename Alloc>

std::multimap< Key, Type, Compare, Alloc >::multimap

(

)

[inline]

Default constructor creates no elements.

Definition at line 162 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

std::multimap< Key, Type, Compare, Alloc >::multimap	(	const Compare &	comp,
		const allocator_type &	a = allocator_type()
	)			[inline, explicit]

Default constructor creates no elements.

Definition at line 170 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

std::multimap< Key, Type, Compare, Alloc >::multimap

(

const multimap< Key, Type, Compare, Alloc > &

x

)

[inline]

Multimap copy constructor.

Parameters:

x

A multimap of identical element and allocator types.

The newly-created multimap uses a copy of the allocation object used by x.

Definition at line 181 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

template<typename InputIterator>

std::multimap< Key, Type, 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 194 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

template<typename InputIterator>

std::multimap< Key, Type, 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 210 of file stl_multimap.h.

---

Member Function Documentation

template<typename Key, typename Type, typename Compare, typename Alloc>

multimap& std::multimap< Key, Type, Compare, Alloc >::operator=

(

const multimap< Key, Type, Compare, Alloc > &

x

)

[inline]

Multimap assignment operator.

Parameters:

x

A multimap of identical element and allocator types.

All the elements of x are copied, but unlike the copy constructor, the allocator object is not copied.

Definition at line 233 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

allocator_type std::multimap< Key, Type, Compare, Alloc >::get_allocator

(

)

const [inline]

Get a copy of the memory allocation object.

Definition at line 241 of file stl_multimap.h.

Referenced by std::multimap< Key, Type, Compare, Allocator >::get_allocator().

template<typename Key, typename Type, typename Compare, typename Alloc>

iterator std::multimap< Key, Type, Compare, Alloc >::begin

(

)

[inline]

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

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 251 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

const_iterator std::multimap< Key, Type, Compare, Alloc >::begin

(

)

const [inline]

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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 260 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

iterator std::multimap< Key, Type, Compare, Alloc >::end

(

)

[inline]

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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 269 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

const_iterator std::multimap< Key, Type, Compare, Alloc >::end

(

)

const [inline]

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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 278 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

reverse_iterator std::multimap< Key, Type, Compare, Alloc >::rbegin

(

)

[inline]

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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 287 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

const_reverse_iterator std::multimap< Key, Type, Compare, Alloc >::rbegin

(

)

const [inline]

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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 296 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

reverse_iterator std::multimap< Key, Type, Compare, Alloc >::rend

(

)

[inline]

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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 305 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

const_reverse_iterator std::multimap< Key, Type, Compare, Alloc >::rend

(

)

const [inline]

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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 314 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

bool std::multimap< Key, Type, Compare, Alloc >::empty

(

)

const [inline]

Returns true if the multimap is empty.

Definition at line 320 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

size_type std::multimap< Key, Type, Compare, Alloc >::size

(

)

const [inline]

Returns the size of the multimap.

Definition at line 325 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

size_type std::multimap< Key, Type, Compare, Alloc >::max_size

(

)

const [inline]

Returns the maximum size of the multimap.

Definition at line 330 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

iterator std::multimap< Key, Type, 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 347 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

iterator std::multimap< Key, Type, Compare, Alloc >::insert	(	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.

See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4 for more on "hinting".

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

Definition at line 371 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

template<typename InputIterator>

void std::multimap< Key, Type, Compare, Alloc >::insert	(	InputIterator	first,
		InputIterator	last
	)			[inline]

A template function that attemps 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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 384 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

void std::multimap< Key, Type, Compare, Alloc >::erase

(

iterator

position

)

[inline]

Erases an element from a multimap.

Parameters:

position

An iterator pointing to the element to be erased.

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 responsibilty.

Definition at line 398 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

size_type std::multimap< Key, Type, 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 responsibilty.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 413 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

void std::multimap< Key, Type, Compare, Alloc >::erase	(	iterator	first,
		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.

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 responsibilty.

Definition at line 428 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

void std::multimap< Key, Type, Compare, Alloc >::swap

(

multimap< Key, Type, Compare, Alloc > &

x

)

[inline]

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.

Definition at line 443 of file stl_multimap.h.

Referenced by std::swap().

template<typename Key, typename Type, typename Compare, typename Alloc>

void std::multimap< Key, Type, Compare, Alloc >::clear

(

)

[inline]

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 responsibilty.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 453 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

key_compare std::multimap< Key, Type, Compare, Alloc >::key_comp

(

)

const [inline]

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

Definition at line 462 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

value_compare std::multimap< Key, Type, 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 470 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

iterator std::multimap< Key, Type, 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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 486 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

const_iterator std::multimap< Key, Type, 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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 501 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

size_type std::multimap< Key, Type, 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 510 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

iterator std::multimap< Key, Type, 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.

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 525 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

const_iterator std::multimap< Key, Type, 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().

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 540 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

iterator std::multimap< Key, Type, 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().

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 550 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

const_iterator std::multimap< Key, Type, 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().

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 560 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

pair<iterator,iterator> std::multimap< Key, Type, 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).

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 577 of file stl_multimap.h.

template<typename Key, typename Type, typename Compare, typename Alloc>

pair<const_iterator,const_iterator> std::multimap< Key, Type, 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).

Reimplemented in __gnu_debug_def::multimap< Key, Type, Compare, Allocator >.

Definition at line 594 of file stl_multimap.h.

---

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

• stl_multimap.h

---