using System;

using System.Diagnostics;

using System.Threading.Tasks;

public class Program

{

    public static void Main()

    {

        var timer = new Stopwatch();

        timer.Start();

        LongTask();

        timer.Stop();

        long ms = timer.ElapsedMilliseconds;

​

        Console.WriteLine(ms.ToString());

    }

    async static void LongTask()

    {

        Task.Delay(2000).Wait();

    }

}