#include <bits/stdc++.h>
using namespace std;
const double Pi = acos(-1.0);
int C[100][6], N;
int main() {
  if (fopen("data.in", "r")) freopen("data.in", "r", stdin);
  scanf("%d", &N);
  C[0][0] = 1;
  for (int i = 1; i <= N; i++) {
    for (int j = 1; j <= min(i, 5); j++)
      C[i][j] = C[i - 1][j - 1] + C[i - 1][j];
    C[i][0] = 1;
  }
  long long ans = C[N][5];
  for (int i = 0; i < 5; i++) ans *= (N - i);
  printf("%I64d", ans);
  return 0;
}
