import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        if(N>=50){
            System.out.println("000000000000");
        }else{
            long Z = 1;
            boolean boo = false;
            long mod = (long)Math.pow(10,12);
            for(int i=1; i<=N; i++){
                Z*=i;
                if(Z>=mod)boo=true;
                Z%=mod;
            }
            if(boo){
                System.out.println(String.format("%012d",Z));
            }else{
                System.out.println(Z);
            }
        }
    }
}