using System;

using System.Diagnostics;

using System.Text;

​

public class Program

{

    private const int counters = 999;

    public static void Main()

    {

        Console.WriteLine("Start");

        Stopwatch sw = new Stopwatch();

        sw.Start();

        Algorithm();

        sw.Stop();

        Console.WriteLine(sw.Elapsed);

        Console.WriteLine("Start Again");

        Stopwatch sw1 = new Stopwatch();

        sw1.Start();

        Algorithm1();

        sw1.Stop();

        Console.WriteLine(sw1.Elapsed);

        Console.WriteLine("See the difference");

    }

​

    private static void Algorithm()

    {

        string result = "";

        for (int i = 0; i <= counters; i++)

        {

            result += i.ToString();

        }

    }

​

    private static void Algorithm1()

    {

        StringBuilder result = new StringBuilder();

        for (int i = 0; i <= counters; i++)

        {

            result.Append(i.ToString());

        }

    }

}