#include<stdio.h>
int main(void){
	long long int N,ans=1;
	scanf("%lld",&N);
	if(N<50){
		for(;N>1;N--){
			ans*=N;
			ans%=1000000000000;
		                     }
		printf("%lld\n",ans);
	                   }  
         else
		{
		printf("000000000000\n");
	         }
	return 0;
}