using System;

public class Program

{

    static int Binom(int n, int k)

{

if (k == 0 || k == n) return 1;

​

else return Binom(n - 1, k) + Binom(n - 1, k - 1);

}

    public static void Main()

    {

        Console.WriteLine( Binom(12, 4));

    }

}