import java.util.Scanner;

public class Main {
	public static void main(String args[]){
		Scanner cin = new Scanner(System.in);
		long N = cin.nextLong();
		cin.close();
		System.out.println(func(N));
	}

	static long func(long n){
		if(n==0L){
			return 1;
		}else{
			return (n*func(n-1))%(long)Math.pow(10, 12);
		}
	}
}