#include <bits/stdc++.h>
using namespace std;
int T;
int main() {
  int n, p = 0, q = 0;
  cin >> n;
  int a[n];
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    if (a[i] > 0)
      p++;
    else if (a[i] < 0)
      q++;
  }
  if (ceil(n / 2.0) <= p)
    cout << "1";
  else if (ceil(n / 2.0) <= q)
    cout << "-1";
  else
    cout << "0";
}
