#include <bits/stdc++.h>
using namespace std;
int cnt[2];
int main() {
  int n;
  cin >> n;
  cnt[0] = cnt[1] = 0;
  for (int i = 1; i <= n; i++) {
    int x;
    cin >> x;
    if (x > 0)
      cnt[0]++;
    else if (x < 0)
      cnt[1]++;
  }
  if (cnt[0] >= (n + 1) / 2)
    cout << 1 << endl;
  else if (cnt[1] >= (n + 1) / 2)
    cout << -1 << endl;
  else
    cout << 0 << endl;
}
