#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9 + 7;
const int inf = 1e9 + 7;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int test = 1;
  while (test--) {
    int n;
    cin >> n;
    long long int C[101][101];
    memset(C, 0, sizeof(C));
    C[0][0] = 1;
    long long int ans;
    for (int i = 1; i <= n; ++i) {
      C[i][0] = 1;
      C[i][i] = 1;
      for (int j = 1; j < i; ++j) C[i][j] = C[i - 1][j - 1] + C[i - 1][j];
    }
    ans = C[n][5] * C[n][5] * (1ll * 120);
    cout << ans;
  }
  return 0;
}
