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