#include <cstdio>
#include <iostream>
using namespace std;
const int D=40000;
const int b=100000;
int n, a[D];
void prod(int v[],int val)
{   int  i, r=0;
    for(i=1; i<=v[0] || r; i++)
    {   v[i] = (val*v[i]+r);
        r = v[i]/b;
        v[i] = v[i]%b;
    }
    v[0] = i - 1;
}
int main()
{   freopen("tamplar.in","r",stdin);
    freopen("tamplar.out","w",stdout);

    a[0] = 1;
    a[1] = 1;

    scanf("%d", &n);

    for(int i=2; i<n; ++i) prod(a,i);

    printf("%d", a[a[0]]);

    for(int i=a[0]-1; i; i--)
        printf("%05d", a[i]);

    return 0;
}