import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.PriorityQueue;
import java.util.Scanner;

public class Main {
	
	public static final long MOD = 1000000000000l;

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		final long N = sc.nextInt();
		
		long value = 1;
		for(long i = 2; i <= N; i++){
			final long next_value = (value * i) % MOD;
			//System.out.println(next_value);
			
			if(value == next_value){
				break;
			}else{
				value = next_value;
			}
		}
		
		System.out.println(value == 0 ? "0" : value);
	}
}