#include <bits/stdc++.h>
const int mod = 1000000007;
const long long INF = 9000000000000000000;
using namespace std;
void solve() {
  long long n;
  cin >> n;
  if (n % 2 != 0)
    cout << 0 << endl;
  else {
    long long x = pow(2, n / 2);
    cout << x << endl;
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long q = 1;
  while (q--) {
    solve();
  }
  return 0;
}
