#include <bits/stdc++.h>
using namespace std;
int main() {
  int n = 0;
  scanf("%d", &n);
  if (n & 1)
    printf("0\n");
  else {
    n /= 2;
    int ans = 1;
    while (n--) ans *= 2;
    cout << ans << endl;
  }
}
