using System;

using System.Collections.Generic;

using System.Threading;

using System.Threading.Tasks;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        MyClass myClass1 =new MyClass();

        MyClass myClass2 =new MyClass();

        MyClass myClass3 =new MyClass();

        Task<int> task1 = Task<int>.Factory.StartNew(()=>myClass1.DoWork());

        Task<int> task2 = Task<int>.Factory.StartNew(()=>myClass2.DoWork());

        Task<int> task3 = Task<int>.Factory.StartNew(()=>myClass3.DoWork());

        int i1= task1.Result;

        int i2 = task2.Result;

        int i3 = task3.Result;

        Console.WriteLine(i1);

        Console.WriteLine(i2);

        Console.WriteLine(i3);

    }

}

​

public class MyClass{

    public static List<int> lst = new List<int>();

     private Mutex mutex = new Mutex(false,"deebujacob.blogspot.com");

    //DoWork with no lock will cause the application to fail

    public int DoWork(){

        mutex.WaitOne();

        try{

            Console.WriteLine("Work started");

            Thread.Sleep(300);

            lst.Add(100);

            Thread.Sleep(100);

            lst.Add(200);

            Thread.Sleep(100);

            lst.Add(300);

            Thread.Sleep(100);

            lst.Add(400);

            Thread.Sleep(100);

            lst.Add(100);

            Thread.Sleep(200);

            lst.Add(200);

            Thread.Sleep(100);

            lst.Add(300);

            Thread.Sleep(100);

            lst.Add(400);

            Thread.Sleep(100);

            Console.WriteLine("Work Complete");

​

        }catch(Exception ex){

            Console.WriteLine(ex);

        }

        finally{

            mutex.ReleaseMutex();

        }

        return lst.Count;

    }

}