#include <bits/stdc++.h>
using namespace std;
long long int exp(long long int x, long long int y) {
  long long int res = 1;
  x = x % (long long int)(1e9 + 7);
  while (y > 0) {
    if (y & 1) res = (res * x) % (long long int)(1e9 + 7);
    y = y >> 1;
    x = (x * x) % (long long int)(1e9 + 7);
  }
  return res;
}
long long int modinv(long long int x) {
  return exp(x, (long long int)(1e9 + 7) - 2);
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long int n, ans = 0;
  cin >> n;
  long long int fac[n];
  fac[0] = 1;
  for (long long int i = 1; i <= n; i++) fac[i] = fac[i - 1] * i;
  long long int res = fac[(n / 2) - 1] * fac[(n / 2) - 1];
  for (long long int mask = 0; mask < (1 << n); ++mask) {
    long long int one = 0, zero = 0;
    for (long long int i = 0; i < n; i++) {
      if (mask & (1 << i))
        one++;
      else
        zero++;
    }
    if (one == zero) ans++;
  }
  ans /= 2;
  ans *= res;
  cout << ans;
  return 0;
}
