// Read N from keybird and output 1*2* ...*N

import java.util.Scanner;

class Fact1_N_a
{
	public static void main(String[] args)
	{
			Scanner input = new Scanner(System.in);

			int N = input.nextInt();
			int f = 1;


			for (int i=1; i<=N; i++)
				f *= i;

			System.out.println ("\nAnswer: " + f + "\n\n\n");
	}
}