#include <bits/stdc++.h>
using namespace std;
int mod = 1e9 + 7;
const long long MAX = 1e18;
const long long MIN = -1e18;
using namespace std;
int main() {
  int n;
  cin >> n;
  if (n % 2)
    cout << 0;
  else
    cout << (1 << n / 2);
}
