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

typedef long long int ln;

void run(void){
  ln n;
  scanf("%lld",&n);

  const ln m=1000000000000LL;
  ln ans=1;
  int k=1;
  while(k<=n && ans>0){
    ans=ans*k%m;
    k++;
  }
  if(ans==0){
    printf("0\n");
  } else {
    printf("%lld\n",ans);
  }
  return;
}

int main(void){
  run();
  return 0;
}