C++ Using STL Map Program

Hello Everyone!

In this tutorial, we will learn about the concept of Map in STL in the C++ programming language.

To understand the basic functionality of the Map Container in STL, we will recommend you to visit C++ STL Map, where we have explained this concept in detail from scratch.

For a better understanding of its implementation, refer to the well-commented C++ code given below.

Code:

#include <iostream>
#include <bits/stdc++.h>

using namespace std;

int main()
{
    cout << "\n\nWelcome to Studytonight :-)\n\n\n";
    cout << " =====  Program to demonstrate the working of a Ordered Map, in CPP  ===== \n\n\n\n";

    cout << "*** Each Element of a Map is a key value par. *** \n\n";

    //Map declaration (Map with key and value both as integers)
    map<int, int> m;

    //Filling the elements by using the insert() method.
    cout << "\n\nFilling the Map with key-value pairs of integers in random order."; //Map automatically stores them in increasing order of keys

    //make_pair() is used to insert a key value pair into the map
    m.insert(make_pair(3, 9));
    m.insert(make_pair(2, 4));
    m.insert(make_pair(5, 25));
    m.insert(make_pair(9, 81));
    m.insert(make_pair(1, 1));

    cout << "\n\nThe number of elements in the Map are: " << m.size();

    cout << "\n\nThe elements of the Map m are: ";

    map<int, int>::iterator i;

    for (i = m.begin(); i != m.end(); i++)
    {
        cout << "\nSquare of " << i->first << " is " << i->second;
    }

    //Initializing a map with the elements of another map

    map<int, int> m1(m.begin(), m.end());

    //Printing the copied map
    cout << "\n\nThe elements of the Map m1 are: ";

    for (i = m1.begin(); i != m1.end(); i++)
    {
        cout << "\nSquare of " << i->first << " is " << i->second;
    }

    cout << "\n\n\n";

    return 0;
}

Output:

We hope that this post helped you develop a better understanding of the concept of the Map Container in STL and its implementation in CPP. For any query, feel free to reach out to us via the comments section down below.

Keep Learning : )