#include<bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n) for (int i=0;i<(n);i++)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)
typedef long long LL;
LL mod=1000000000000;

LL kaizyou(LL N){
   if(N==1)return 1;
   return (N*kaizyou(N-1))%mod;
}
int main(){
        LL N;
	cin>>N;
	if(N>50){
	    printf("000000000000\n");
	}else{
           printf("%lld\n",kaizyou(N));
        }
	return(0);
}