StringEncryption.cpp

#include <iostream>

using namespace std;

int main()
{
    int i, x;
    char str[100];

    cout << "Please enter a String: \t";
    cin >> str;

    cout << "\n Please Choose The Following Options: \n";
    cout << "[1] ENCRYPT STRING. \n";
    cout << "[2] DECRYPT STRING. \n";

    cin >> x;

    switch (x)
    {
    case 1:
        for (i = 0; (i < 100 && str[i] != '\0'); i++)
        {
            str[i] = str[i] + 2; //the key for encryption is 3 that is added to ASCII value
        }

        cout << "\nEncrypted string: " << str << endl;
        break;

    case 2:
        for (i = 0; (i < 100 && str[i] != '\0'); i++)
        {
            str[i] = str[i] - 2; //the key for encryption is 3 that is subtracted to ASCII value
        }

        cout << "\nDecrypted string: " << str << endl;
        break;

    default:
        cout << "\nInvalid Input !!!\n";
    }

    return 0;
}