package yukicoder;

import java.util.Scanner;

public class N500
{
	public static void main(String[] args)
	{
		Scanner sc=new Scanner(System.in);
		long N=sc.nextLong();
		long ans =1;
		for(int i=2;i<=N;i++)
		{
			ans*=i;
			ans%=(long)Math.pow(10, 12);
		}
		System.out.println(ans);
	}
}