#include <bits/stdc++.h>
using namespace std;
long long n, ans, i, now;
int main() {
  scanf("%lld", &n);
  now = 1;
  for (i = 1; i <= 5; i++) now = now * (n - i + 1) / i;
  ans = now * now * 120;
  printf("%lld", ans);
}
