function to take y/ n char input

// function to take y/ n char input
char input_char_y_or_n()
{
    char entered_letter = 'x';
    do
        {
            std::cout << "\tRepeat Program ? (enter y/n):  ";
            std::cin >> entered_letter;
        } while ( entered_letter != 'y' && entered_letter != 'Y' &&  entered_letter != 'n' && entered_letter != 'N'  );

    return entered_letter;
}