#include <bits/stdc++.h>
const long long INF = 0x3f3f3f3f3f3f3f;
const long long NINF = -INF - 1;
using namespace std;
int a[110];
int main() {
  ios::sync_with_stdio(false);
  int n, t = 0, t1 = 0, max = 0;
  cin >> n;
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
    if (a[i] > 0) {
      t++;
    } else if (a[i] < 0)
      t1++;
  }
  int l = n / 2;
  if (n % 2 == 1) l++;
  if (t >= l)
    cout << "1" << endl;
  else if (t1 >= l)
    cout << "-1" << endl;
  else
    cout << "0" << endl;
  return 0;
}
