#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n, p = 0, ne = 0;
  cin >> n;
  int arr[n];
  for (int i = 0; i < n; i++) {
    cin >> arr[i];
    if (arr[i] > 0) p++;
    if (arr[i] < 0) ne++;
  }
  if (n % 2 == 0)
    n /= 2;
  else {
    n /= 2;
    n++;
  }
  if (p >= n) {
    cout << "1";
    return 0;
  }
  if (ne >= n) {
    cout << "-1";
    return 0;
  }
  cout << "0";
}
