#include <bits/stdc++.h>
using namespace std;
long long MOD = 1000000007;
long long pw(long long a, long long b) {
  long long r = 1;
  while (b > 0) {
    if (b & 1) {
      r = (r * a) % MOD;
    }
    b = b >> 1;
    a = (a * a) % MOD;
  }
  return (r) % MOD;
}
int main() {
  long long n;
  scanf("%lld", &n);
  double ans = 1;
  for (int i = 0; i < 5; i++) {
    ans *= (n - i);
  }
  ans /= 120;
  for (int i = 0; i < 5; i++) {
    ans *= (n - i);
  }
  cout << (long long)ans;
  printf("\n");
  return 0;
}
