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