#include<stdio.h>


int main(int argc, char const *argv[]){
	long long n,ans=1,i;
	scanf("%lld",&n);
	for(i=1;i<=n;i++){
		ans*=i%1000000000000;
		ans%=1000000000000;
	}
	printf("%lld\n",ans);
	return 0;
}