multimap::count() method in C++ STL

Multimaps are associative containers available in the C++ Standard Library. They are similar to a map with an addition that multiple elements can have the same keys. The multimap::count() is a method available in the STL that counts the number of elements with a specific key.

Syntax:

map_name.count(val);

Parameters: The multimap::count() accepts a single parameter:
• val: Key to search for
Return value: The number of elements that have key equal to val

Example of multimap::count() method

#include<iostream>
#include<map>

using namespace std;

int main()
{
    multimap<char,int> m;

    m.insert( pair<int,int> ('a',1) );
    m.insert( pair<int,int> ('b',2) );
    m.insert( pair<int,int> ('c',3) );
    m.insert( pair<int,int> ('a',4) );

    cout<<"Number of elements with key 'a' are: "<< m.count('a');
}

Output:

Number of elements with key 'a' are: 2