#include <bits/stdc++.h>
using namespace std;
long long int poo(long long int x) {
  if (x == 0) {
    return 1;
  } else {
    return 2 * poo(x - 1);
  }
}
int main() {
  int n;
  cin >> n;
  if (n % 2 != 0) {
    cout << "0";
  } else {
    cout << poo(n / 2);
  }
  return 0;
}
