class combinatoria
{
	public static void main(String arg[ ])
	{
		System.out.println("C(5,3) : " + combinatoria(5,3));
		System.out.println("C(6,3) : " + combinatoria(6,3));
		System.out.println("C(8,5) : " + combinatoria(8,5));
		System.out.println("C(9,4) : " + combinatoria(9,4));
		System.out.println("C(2,1) : " + combinatoria(2,1));
	}

	public static long combinatoria(int n, int x )
	{
		int dif, term;
		double comb = 1; 
   
		dif =  Math.max(x , n - x);
		term = Math.min(x , n - x);
		for (int i = 1;  i <= term ; i++)  
		{
			comb *= (double) ( i + dif ) / i;
		}
   
		return (long) comb;
	}
}