Multisets are associative containers available in the C++ Standard Library. They are similar to sets with an addition that multiple keys with equivalent values are allowed. The multiset::count() is a method available in the STL that counts the number of elements with a specific key.
Syntax:
set_name.count(val);
Parameters: The multiset::count() accepts a single parameter:
• val: Key to search for
Return value: The number of elements that have key equal to val
Example of multiset::count() method
#include <iostream>
#include <set>
using namespace std;
int main()
{
multiset<int> m;
m.insert(1);
m.insert(2);
m.insert(2);
m.insert(2);
m.insert(3);
m.insert(4);
cout<<"Key 2 is repeated: "<<m.count(2)<<" times"<<endl;
}
Output:
Key 2 is repeated: 3 times
