#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n;
  cin >> n;
  int cp = 0, cn = 0;
  for (int i = 0; i < n; ++i) {
    int t;
    cin >> t;
    if (t > 0) {
      cp++;
    } else if (t < 0) {
      cn++;
    }
  }
  int pro = (int)ceil(n / 2.0);
  if (cp >= pro)
    cout << 1 << endl;
  else if (cn >= pro)
    cout << -1 << endl;
  else
    cout << 0 << endl;
  return 0;
}
