#include <bits/stdc++.h>
using namespace std;
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  long long n;
  cin >> n;
  if (n % 2 == 1)
    cout << 0;
  else
    cout << (long long)pow(2, n / 2);
}
