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std::multiset count() method

// (1) Const version only
size_type count( const Key& key ) const;

// (2) Const version only
template< class K >
size_type count( const K& x ) const;

Returns the number of elements with key that compares equivalent to the specified argument.

  • (1) Returns the number of elements with key key.
  • (2) Returns the number of elements with key that compares equivalent to the value x. This overload participates in overload resolution only if the qualified-id Compare::is_transparent is valid and denotes a type. They allow calling this function without constructing an instance of Key.

Parameters​

  • key - key value of the elements to count
  • x - alternative value to compare to the keys

Return value​

Number of elements with key that compares equivalent to key or x.

Complexity​

Logarithmic in the size of the container plus linear in the number of the elements found - O(log size() + N), where N is the number of elements found.

Exceptions​

(none)

Example​

important

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std::multiset count() method

// (1) Const version only
size_type count( const Key& key ) const;

// (2) Const version only
template< class K >
size_type count( const K& x ) const;

Returns the number of elements with key that compares equivalent to the specified argument.

  • (1) Returns the number of elements with key key.
  • (2) Returns the number of elements with key that compares equivalent to the value x. This overload participates in overload resolution only if the qualified-id Compare::is_transparent is valid and denotes a type. They allow calling this function without constructing an instance of Key.

Parameters​

  • key - key value of the elements to count
  • x - alternative value to compare to the keys

Return value​

Number of elements with key that compares equivalent to key or x.

Complexity​

Logarithmic in the size of the container plus linear in the number of the elements found - O(log size() + N), where N is the number of elements found.

Exceptions​

(none)

Example​

important

This section requires improvement. You can help by editing this doc page.

This article originates from this CppReference page. It was likely altered for improvements or editors' preference. Click "Edit this page" to see all changes made to this document.
Hover to see the original license.