#include <bits/stdc++.h>
using namespace std;
long long dp[5105];
int a[4] = {2, 3, 5, 7};
int main() {
  int i, n;
  long long s = 1;
  cin >> n;
  for (i = n; i >= n - 4; i--) {
    s = s * i;
    s = s / (n - i + 1);
  }
  s = s * s;
  s = s * 120;
  cout << s << endl;
}
