Swapping of 2 Numbers without using 3rd Number

//Swapping of 2 Numbers without using 3rd number
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace cs3
{
    class Program
    {
        static void Main(string[] args)
        {
            int x,y;
            Console.WriteLine("Enter any 2 Numbers");
            x = int.Parse(Console.ReadLine());
            y = int.Parse(Console.ReadLine());
            Console.WriteLine("Before Swapping the Numbers are");
            Console.Write("First Number:" + x);
            Console.Write("\tSecond Number:" + y);
            x = x + y;
            y = x - y;
            x = x - y;
            Console.WriteLine("\n\nAfter Swapping the Numbers are");
            Console.Write("First Number:" + x);
            Console.Write("\tSecond Number:" + y);
            Console.ReadLine();

        }
    }
}