Input a double

using System;
class Program
{
    public static void Main(String[] args)
    {
        string a, b;
        double x, y;
        a = Console.ReadLine();
        b = Console.ReadLine();
        x = double.Parse(a);
        y = double.Parse(b);
        double res = x + y;
        Console.WriteLine("The Addition is: " + res);
        Console.ReadKey();
    }
}