#include <bits/stdc++.h>
using namespace std;
void solve() {
  long long n;
  cin >> n;
  if (n % 2) {
    cout << 0;
    return;
  }
  cout << (long long)pow(2, n / 2);
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  long long t = 1;
  while (t--) solve();
}
