#include <bits/stdc++.h>
using namespace std;
int gcd(int a, int b) {
  if (a == 0)
    return b;
  else
    return gcd(b % a, a);
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int n;
  cin >> n;
  if (n & 1)
    cout << 0 << endl;
  else
    cout << (1 << (n / 2)) << endl;
}
