import java.math.*;
import java.io.*;
public class Binomial
{

        private static BufferedReader stdin = new BufferedReader( new InputStreamReader( System.in ) );

	// This is the classic, recursive implementation of a function
	// that computed the nth Fibonacci number (given n)
        public static int binomial(int n, int k)
        {
		if(n < k)
			return 0;

                if(n == k)
                        return 1;

		if(k == 1)
			return n;

		if(k == 0)
			return 1;

               	return binomial(n-1, k) + binomial(n-1, k-1);
        }


        public static void main(String[] args)
        {

                int n;
		long time, newTime, answer;
	
                // Prompt the user
                System.out.println("Type two positive integers." );
                try{

                        // Read a line of text from the user.
                        String input = stdin.readLine();

                        // converts a String into an int value
                        n = Integer.parseInt( input );

                        // Read a line of text from the user.
                        input = stdin.readLine();

                        // converts a String into an int value
                        int k = Integer.parseInt( input );
			
			time = System.currentTimeMillis();
			answer = binomial(n, k);
			newTime = System.currentTimeMillis();

                        System.out.println("The binomial number is "+ answer);
                        System.out.println("It took " + (newTime-time) + " milliseconds to compute it.");
                }
                catch(java.io.IOException e)
                {
                        System.out.println(e);
                }

		

	} // end of main
	
} // end of class