#include <bits/stdc++.h>
using namespace std;
int n;
vector<int> v;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cin >> n;
  v = vector<int>(n);
  int pos = 0, neg = 0;
  for (int i = 0; i < n; i++) {
    cin >> v[i];
    if (v[i] > 0) pos++;
    if (v[i] < 0) neg++;
  }
  n = (n + 1) / 2;
  if (pos >= n)
    cout << "1" << endl;
  else if (neg >= n)
    cout << "-1" << endl;
  else
    cout << "0" << endl;
}
