#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:64000000")
using namespace std;
const double PI = 6.283185307179586476925286766559;
const int MAXN = 100100, root = 256;
string a, res;
long long n;
int x1, x2, y3, y2;
long long c[10000][10];
void solve() {
  for (int i = 0; i < 10000; ++i) {
    if (i < 10) c[i][i] = 1;
    c[i][0] = 1;
    for (int j = 1; j < min(i, 10); ++j)
      c[i][j] = c[i - 1][j] + c[i - 1][j - 1];
  }
  cin >> n;
  long long ans = 1;
  cout << c[n][5] * c[n][5] * 120;
  ;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  srand(time(0));
  solve();
  return 0;
}
