#include <bits/stdc++.h>
int main() {
  unsigned long long no_of_paths;
  unsigned long long no_of_arrangements;
  scanf("%I64u", &no_of_paths);
  no_of_arrangements = (no_of_paths) * (no_of_paths - 1) / 2 *
                       (no_of_paths - 2) / 3 * (no_of_paths - 3) / 4 *
                       (no_of_paths - 4) / 5;
  no_of_arrangements *= (no_of_paths) * (no_of_paths - 1) * (no_of_paths - 2) *
                        (no_of_paths - 3) * (no_of_paths - 4);
  printf("%I64u\n", no_of_arrangements);
  return 0;
}
