#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int t = (n + 1) / 2;
  int cnt1 = 0;
  int cnt2 = 0;
  for (int i = 0; i < n; i++) {
    int a;
    cin >> a;
    if (a > 0) cnt1++;
    if (a < 0) cnt2++;
  }
  if (cnt1 >= t)
    cout << 1 << endl;
  else if (cnt2 >= t)
    cout << -1 << endl;
  else
    cout << 0 << endl;
  return 0;
}
