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