#include <bits/stdc++.h>
const int mod = 1000000007;
const int inf = 1000000009;
const long long int INF = 1000000000000000009;
const long long big = 1000000000000000;
const long double eps = 0.0000000001;
using namespace std;
int main() {
  int n;
  cin >> n;
  long long int wynik = 1;
  if (n & 1) {
    cout << 0;
    return 0;
  }
  for (int i = 1; i <= n / 2; i++) wynik *= 2;
  cout << wynik;
  return 0;
}
