#include <bits/stdc++.h>
using namespace std;
const int M = 1e9 + 7;
int main() {
  long long n;
  cin >> n;
  if (n % 2LL) {
    cout << 0 << endl;
    return 0;
  } else {
    cout << (1LL << (n / 2LL)) << endl;
  }
  return 0;
}
