#include <bits/stdc++.h>
using namespace std;
int n;
int a[110];
int x, y;
int main() {
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    if (a[i] > 0)
      x++;
    else if (a[i] < 0)
      y++;
  }
  if (x >= (n + 1) / 2)
    cout << "1";
  else if (y >= (n + 1) / 2)
    cout << "-1";
  else
    cout << "0";
  return 0;
}
