#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int i, j = 0, k = 0, l = 0, xt, yt, x, y, x1, x2, y1, y2, s = 0,
                   c = 0;
  double n;
  cin >> n;
  int arr[1000];
  for (i = 0; i < n; i++) {
    cin >> arr[i];
    if (arr[i] > 0)
      j++;
    else if (arr[i] < 0)
      k++;
    else
      l++;
  }
  if (j >= ceil(n / 2))
    cout << 1;
  else if (k >= ceil(n / 2))
    cout << -1;
  else
    cout << 0;
  return 0;
}
