import java.util.Scanner;

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

		long N = cin.nextLong();

		System.out.println(func(N));
	}

	static long func(long n){

		if(n==0){
			return 1;
		}else{
			return n*func(n-1)%(long)Math.pow(10, 13);
		}

	}
}