Unordered Multimap Size Function in C++ STL

unordered_multimap size() function in C++ STL returns the number of elements in the unordered map.

Algorithm

Begin
   Declare an empty map container m.
   Performing reserve function to restrict the most appropriate
   bucket_count of the map container.
   Insert values in the map container.
   Print the size of the unorderd multimap container by using the size() function.
End

Example Code

 Live Demo

#include<iostream>
#include <bits/stdc++.h>
using namespace std;

int main() {
   unordered_map<char, int> m; // declaring m as empty map container

   m.reserve(6); //restricting the most appropriate bucket_count of map container
   m.insert (pair<char, int>('b', 10)); // inserting some values
   m.insert (pair<char, int>('a', 20));

   cout << "The size is: " << m.size(); //printing the size of unordered multimap container by size() function.

   return 0;
}

Output

The size is :2