#include <bits/stdc++.h>
using namespace std;
const int N = 3e5 + 5;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int n, cntp = 0, cntn = 0;
  cin >> n;
  for (int i = 0; i < n; i++) {
    int x;
    cin >> x;
    if (x > 0)
      cntp++;
    else if (x < 0)
      cntn++;
  }
  if (cntp >= (n + 1) / 2)
    cout << 1 << endl;
  else if (cntn >= (n + 1) / 2)
    cout << -1 << endl;
  else
    cout << 0 << endl;
  return 0;
}
