using System;

using System.Threading;

​

class Program

{

    private static readonly object _lockObject = new object();

    private static int _counter = 0;

​

    static void Main()

    {

        Thread thread1 = new Thread(IncrementCounter);

        Thread thread2 = new Thread(IncrementCounter);

​

        thread1.Start();

        thread2.Start();

​

        thread1.Join();

        thread2.Join();

​

        Console.WriteLine($"Final counter value: {_counter}");

    }

​

    private static void IncrementCounter()

    {

        for (int i = 0; i < 1000; i++)

        {

            lock (_lockObject)

            {

                _counter++;

            }

        }

    }

}

​