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