double input_double_range()

double input_double_range()
{
    bool valid_input = false;
    double n;

    do
    {
        std::cout << " (enter number between 0 and 24): ";
        std::cin >> n;
        if (0 <=n && n <=24 )
        {
            valid_input = true;
        }
        else // Error statement
        {
            valid_input = false;
            cout << "You have not entered a valid input" << endl
                 << endl;
        }
    } while(valid_input == false);
    return n;
}