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