using System;

using System.Linq;

using System.Collections.Generic;

using System.Threading;

public class Program

{

    public static void Main()

    {

        Random rnd = new Random();

        Statistics stats = new();

        var threads = new List<Thread>();

        for( int i = 0; i < 10; i++ )

        {

            if( i % 2 == 0 )

            {

            threads.Add(new Thread(() => {

              Thread.Sleep(rnd.Next(100, 700)*10);

              stats.Counter1.Increment();

              }));

            }

            else

            {

            threads.Add(new Thread(() => {

              Thread.Sleep(rnd.Next(100, 700)*10);

              stats.Counter2.Increment();

              }));

            }

        }

        threads.ForEach(x => x.Start());

        for(int a = 0; a < 50; a++)

        {

            Thread.Sleep(100);

            Console.WriteLine(stats);

        }

​

        stats.Counter1.Reset();

        Console.WriteLine(stats);

        for(int a = 0; a < 50; a++)

        {

            Thread.Sleep(100);

            Console.WriteLine(stats);

        }

        foreach( var thread in threads ) thread.Join();

    }

}

​

public sealed class Statistics

{

    public Counter Counter1 {get;} = new Counter();

    public Counter Counter2 {get;} = new Counter();

    public override string ToString() => $"C1: {Counter1.Get()}, C2: {Counter2.Get()}";

}

​

public sealed class Counter

{

    private int _count = 0;

    public void Increment()

    {

        _ = Interlocked.Increment(ref _count);

    }

    public void Reset()

    {

        _ = Interlocked.Exchange(ref _count, 0);

    }

    public int Get()

    {

        // Read operation on Int32 is already atomic.

        return _count;

    }

}