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