#include <bits/stdc++.h>
using namespace std;
int main() {
  int t, t1;
  cin >> t;
  t1 = ceil(float(t) / 2);
  int p = 0, n = 0, z = 0;
  while (t--) {
    int a;
    cin >> a;
    if (a)
      a > 0 ? p++ : n++;
    else
      z++;
  }
  if (p >= t1)
    cout << "1";
  else if (n >= t1)
    cout << "-1";
  else
    cout << "0";
  return 0;
}
