using System;
   using System.Collections.Generic;
   using System.Text;
   using System.Threading;


   namespace ConsoleApplication1
   {
       



   public class Buffer
   {
         private Pair   data; 
         private bool  empty = true;

         public void Read(ref Pair data)
         {
            lock(this)
            {
               // Check whether the buffer is empty.
               if (empty)
                  Monitor.Wait(this);
               empty = true;
               data.key = this.data.key;
               data.colour = this.data.colour;
               data.trace("    read :");
               Monitor.Pulse(this);
            }
         }

         public void Write(Pair data)
         { 
            lock(this)
            {  
               // Check whether the buffer is full.
               if (!empty)
                  Monitor.Wait(this);
               empty = false;
               this.data.key = data.key;
               this.data.colour = data.colour;
               this.data.trace("wrote :");
               Monitor.Pulse(this);
            }
         }
         
         public void Start()
         {
         }

   }// end class Buffer

   public class Producer
   {
      private Buffer buffer;
      private Random random = new Random();

      public Producer(Buffer buffer)
      {
          this.buffer = buffer;

      }

      public void Production()
      {
          Pair p = new Pair(0, 0);
          for(int i=1; i<=10; i++) 
          {
            // delay up to 500 milliseconds.
            Thread.Sleep(random.Next(501));
            p.key = i; p.colour = i;
            buffer.Write(p);
          }
      }
   }

   public class Consumer
   {
      private Buffer buffer;
      private Random random = new Random();

      public Consumer(Buffer buffer)
      {
          this.buffer = buffer;

      }

      public void Consumption()
      { 
          Pair data = new Pair(0,0);
          string hold_up;
          for(int i=1; i<=10; i++) 
          {
            // delay up to 500 milliseconds.
            Thread.Sleep(random.Next(501));
            buffer.Read(ref data);
          }
          Console.WriteLine("\nplease return to terminate");
          hold_up =Console.ReadLine();
      }
   }

      public struct Pair
      {
         public int key       ;
         public int colour  ;

         public Pair(int key,
                     int colour)
         {
            this.key = key;
            this.colour = colour;
         }

         public void trace(string s)
         {
           Console.Write(s +" key : " + key );
           Console.WriteLine(" colour : " + colour);
         }
      }

   public class TheOne 
   {
     public static void Main()
     {
        Buffer   buff = new Buffer();
        Producer prod = new Producer(buff);
        Consumer con  = new Consumer(buff);
      
       Thread ProducerThread = new Thread(new ThreadStart(
        prod.Production));
        Thread ConsumerThread = new Thread(new ThreadStart(
        con.Consumption));

        ProducerThread.Start();
        ConsumerThread.Start();
       
       
       
     }
   }


   }