#include <bits/stdc++.h>
using namespace std;
bool b2(const pair<pair<int, int>, int> &p1,
        const pair<pair<int, int>, int> &p2) {
  return p1.first.first > p2.first.first;
}
bool b1(const pair<pair<int, int>, int> &p1,
        const pair<pair<int, int>, int> &p2) {
  return p1.first.second < p2.first.second;
}
int gcd(int a, int b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
int main() {
  int n;
  cin >> n;
  if (n % 2 == 0)
    cout << (1 << (n / 2)) << endl;
  else
    cout << "0" << endl;
  return 0;
}
