Convert a sentence into its equivalent mobile numeric keypad sequence

 Convert a sentence into its equivalent mobile numeric keypad sequence-Data Structure and Algorithms

Given a sentence in the form of a string, convert it into its equivalent mobile numeric keypad sequence

Input : STRIVE
Output : 7777877744488833
For obtaining a number, we need to press a
number corresponding to that character for 
number of times equal to position of the 
character. For example, for character C, 
we press number 2 three times and accordingly.

Input : HELLO WORLD
Output : 4433555555666096667775553

Solution:

// #include <iostream>

#include <bits/stdc++.h>

using namespace std;

int main()

{

    // cout<<"Hello World!";

    string s[] = {"2", "22", "222",

                  "3", "33", "333",

                  "4", "44", "444",

                  "5", "55", "555",

                  "6", "66", "666",

                  "7", "77", "777", "7777",

                  "8", "88", "888",

                  "9", "99", "999", "9999"};

    string input;

    cin >> input;

    string ans = "";

    for (int i = 0; i < input.length(); i++)

    {

        if (input[i] == ' ')

            ans += '0';

        else

        {

            int idx = input[i] - 'A';

            ans += s[idx];

        }

    }

    cout << ans << endl;

    return 0;

}

Thank You