#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int sim = (n / 2);
  if (n % 2) sim++;
  int pl = 0, mi = 0, x;
  for (int i = 0; i < n; i++) {
    cin >> x;
    if (x > 0)
      pl++;
    else if (x < 0)
      mi++;
  }
  if (pl >= sim)
    cout << 1 << endl;
  else if (mi >= sim)
    cout << -1 << endl;
  else
    cout << 0 << endl;
  return 0;
}
