using System;

using  System.Web;

using System.Threading.Tasks;

public class Program

{

    public static void Main()

    {

        int iterations = 10000000;

        Me(iterations);

        Them(iterations);

    }

    public static void Me(int iterations){

        var a = 10;

        var b = 20;

        DateTime begin = DateTime.UtcNow;

        for(int i= 0; i< iterations;i++){

            var temp = a;

            a=b;

            b=temp;

        }

        DateTime end = DateTime.UtcNow;

        Console.WriteLine("Measured time: " + (end-begin).TotalMilliseconds + " ms.");

    }

    public static void Them(int iterations){

        var a = 10;

        var b = 20;

        DateTime begin = DateTime.UtcNow;

        for(int i= 0; i< iterations;i++){

            a = a ^ b;

            b = a ^ b;

            a = a ^ b;

        }

        DateTime end = DateTime.UtcNow;

        Console.WriteLine("Measured time: " + (end-begin).TotalMilliseconds + " ms.");

    }

}