using System;

​

public class MyPi : Random

{

    public long Iteration {get; private set;}

    private long _accumulator;

    public MyPi()

    {

        Iteration = 0L;

        _accumulator = 0L;

    }

    public double Estimate()

    {

        ++Iteration;

        return Sample();

​

    }

}

​

public class Program

{

    public static void Main()

    {

        var pi = new MyPi();

        do { pi.Estimate(); } while( pi.Iteration < 5e5);

        Console.WriteLine(pi.Estimate());

    }

}