#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, positive, negative, zero, a, b, c;
  cin >> n;
  positive = 0;
  negative = 0;
  zero = 0;
  for (a = 0; a < n; a++) {
    cin >> b;
    if (b > 0) positive++;
    if (b < 0)
      negative++;
    else
      zero++;
  }
  c = (n + 1) / 2;
  if (positive >= c)
    cout << "1" << endl;
  else if (negative >= c)
    cout << "-1" << endl;
  else
    cout << "0" << endl;
  return 0;
}
