using System;

using System.Threading;

​

namespace Program

{

    public class Program

    {

        public static void Main(string[] args)

        {

            int i = 5;

            bool wasTaken = false;

            try{

                Monitor.Enter(i, ref wasTaken);

            }finally{

                if(wasTaken){

                    Monitor.Exit(i);

                }

            }

        }

    }

}

​