#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int pos = 0, neg = 0, x;
  for (int i = 0; i < n; i++) {
    cin >> x;
    if (x > 0) {
      pos++;
    }
    if (x < 0) {
      neg++;
    }
  }
  double req = ceil(double(n) / 2);
  if (pos >= req) {
    cout << "1";
  } else if (neg >= req) {
    cout << "-1";
  } else {
    cout << "0";
  }
}
