#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3", "unroll-loops")
long long mod = 1e9 + 7;
int32_t main() {
  ;
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  ;
  cout << fixed << setprecision(20);
  ;
  long long n;
  cin >> n;
  if (n % 2 == 0)
    cout << (1 << (n / 2)) << endl;
  else
    cout << 0 << endl;
  return 0;
}
