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