#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, temp, positive = 0, negative = 0, lowest;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> temp;
    positive += temp > 0;
    negative += temp < 0;
  }
  lowest = ceil((double)n / 2);
  cout << (positive >= lowest ? "1" : (negative >= lowest ? "-1" : "0"))
       << endl;
  return 0;
}
