using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading;

using System.Threading.Tasks;

​

//Mohamed Elmadhoun

​

public class Program

{

    public static void Main()

    {

        const int n = 5;

        var chopsticks = new Dictionary<int, object>(n);

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

        {

            chopsticks.Add(i, new object ());

        }

​

        Task[] myactions = new Task[n];

        myactions[0] = new Task(() => Person.Eat(chopsticks[0], chopsticks[n - 1], 1, 1, n));

        for (int i = 1; i < n; ++i)

        {

            int j = i;

            myactions[j] = new Task(() => Person.Eat(chopsticks[j - 1], chopsticks[j], j++, j, j++));

        }

​

        Parallel.ForEach(myactions, t =>

        {

            t.Start();

        }

​

        );

        Task.WaitAll(myactions);

        Console.WriteLine("\nEveryone finished eating.");

    }

}

​

public class Person

{

    static public void Eat(object leftchopstick, object rightchopstick, int personnumber, int leftchopsticknumber, int rightchopsticknumber)

    {

        lock (leftchopstick)

        {

            Console.WriteLine("Person {0} picked chopstick number {1}", personnumber, leftchopsticknumber);

            lock (rightchopstick)

            {

                Console.WriteLine("Person {0} picked chopstick number {1}", personnumber, rightchopsticknumber);

                Console.WriteLine("Person {0} eats", personnumber);

                Thread.Sleep(1000);

            }

            Console.WriteLine("Person {0} released chopstick number {1}", personnumber, rightchopsticknumber);

        }

        Console.WriteLine("Person {0} released chopstick number {1}", personnumber, rightchopsticknumber);

    }

}