#include <cstdio>
#include <iostream>
#include <cstring>
#include <map>
#include <algorithm>
using namespace std;
typedef long long ll;
const int MAXN=40000;
int ans[MAXN];
int flag;
int main()
{
    int n,r,tmp;
while(scanf("%d",&n)!=EOF){
    flag=0;
     memset(ans,0,sizeof(ans));
     ans[0]=1;
     for(int i=2;i<=n;i++)
     {
         r=0;
        for(int j=0;j<=MAXN;j++)
        {
            tmp=ans[j]*i+r;
            ans[j]=tmp%10;
            r=tmp/10;

        }
     }
       for(int i=MAXN;i>=0;i--)
       {
          if(flag==0&&ans[i]==0)
          continue;
          else
          {
              flag=1;
              printf("%d",ans[i]);
          }
       }
       printf("\n");
    }
    return 0;
}