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std::flat_set::count(3) C++ Standard Libary std::flat_set::count(3)

NAME

std::flat_set::count - std::flat_set::count

Synopsis


size_type count( const Key& key ) const; (1) (since C++23)
template< class K > (2) (since C++23)
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. This is either 1 or 0 since this
container does not allow duplicates.
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. It allows 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, which, for
overload (1), is either 1 or 0.

Complexity


Logarithmic in the size of the container plus linear in the number of elements
found.

Example


This section is incomplete
Reason: no example

See also


find finds element with specific key
(public member function)
equal_range returns range of elements matching a specific key
(public member function)

Category:


* Todo no example

2024.06.10 http://cppreference.com