#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  if (n % 2 == 1)
    cout << 0 << endl;
  else {
    long long int tt = 1;
    tt = pow(2, n / 2);
    cout << tt << endl;
  }
  return 0;
}
