Lookup

All methods in this section can be executed concurrently with each other, concurrently-safe modifiers and while traversing the container.

count

size_type count( const key_type& key );

Returns: the number of elements with the key equal to key.

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template <typename K>
size_type count( const K& key );

Returns: the number of elements with the key which compares equivalent with key.

This overload only participates in overload resolution if qualified-id key_compare::is_transparent is valid and denotes a type.

find

iterator find( const key_type& key );

const_iterator find( const key_type& key ) const;

Returns: an iterator to the element with the key equal to key or end() if no such element exists.

If there are multiple elements with the key equal to key exists, it is unspecified which element should be found.

---

template <typename K>
iterator find( const K& key );

template <typename K>
const_iterator find( const K& key ) const;

Returns: an iterator to the element with the key which compares equivalent with key or end() if no such element exists.

If there are multiple elements with the key which compares equivalent with key exists, it is unspecified which element should be found.

These overloads only participates in overload resolution if qualified-id key_compare::is_transparent is valid and denotes a type.

contains

bool contains( const key_type& key ) const;

Returns: true if an element with the key equal to key exists in the container, false otherwise.

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template <typename K>
bool contains( const K& key ) const;

Returns: true if an element with the key which compares equivalent with key exists in the container, false otherwise.

This overload only participates in overload resolution if qualified-id key_compare::is_transparent is valid and denotes a type.

lower_bound

iterator lower_bound( const key_type& key );

const_iterator lower_bound( const key_type& key ) const;

Returns: an iterator to the first element in the container with the key which is not less than key.

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template <typename K>
iterator lower_bound( const K& key )

template <typename K>
const_iterator lower_bound( const K& key ) const

Returns: an iterator to the first element in the container with the key which compares not less with key.

These overloads only participates in overload resolution if qualified-id key_compare::is_transparent is valid and denotes a type.

upper_bound

iterator upper_bound( const key_type& key );

const_iterator upper_bound( const key_type& key ) const;

Returns: an iterator to the first element in the container with the key which is greater than key.

---

template <typename K>
iterator upper_bound( const K& key );

template <typename K>
const_iterator upper_bound( const K& key ) const;

Returns: an iterator to the first element in the container with the key which compares greater with key.

These overloads only participates in overload resolution if qualified-id key_compare::is_transparent is valid and denotes a type.

equal_range

std::pair<iterator, iterator> equal_range( const key_type& key );

std::pair<const_iterator, const_iterator> equal_range( const key_type& key ) const;

Returns: if at least one element with the key equal to key exists - a pair of iterators {f, l}, where f is an iterator to the first element with the key equal to key, l is an iterator to the element which follows the last element with the key equal to key. Otherwise - {end(), end()}.

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template <typename K>
std::pair<iterator, iterator> equal_range( const K& key )

template <typename K>
std::pair<const_iterator, const_iterator> equal_range( const K& key )

Returns: if at least one element with the key equal to key exists - a pair of iterators {f, l}, where f is an iterator to the first element with the key which compares equivalent with key, l is an iterator to the element which follows the last element with the key which compares equivalent with key. Otherwise - {end(), end()}.

These overloads only participates in overload resolution if qualified-id key_compare::is_transparent is valid and denotes a type.