#include <stdio.h>
#include <math.h>
#include <stdlib.h>

int main(void){
	unsigned long long n;
	scanf("%llu",&n);
	if(n>=50){
		printf("000000000000\n");
		return 0;
	}
	int i;
	unsigned long long dp[n+1];
	dp[0]=1;dp[1]=1;
	for(i=2;i<n+1;i++){
		dp[i]=(dp[i-1]*i)%1000000000000;
	}
	printf("%llu\n",dp[n]);
	return 0;
}