#include <bits/stdc++.h>
using namespace std;
vector<int> abj[10000];
bool visided[10000];
void dfs(int x) {
  vector<int> v = abj[x];
  if (visided[x] == false) {
    visided[x] = true;
    for (int i = 0; i < v.size(); i++) {
      dfs(v[i]);
    }
  }
}
int main() {
  int x;
  cin >> x;
  int arr[x];
  int p = 0, n = 0;
  int s = ceil(x / (2.0));
  for (int i = 0; i < x; i++) {
    cin >> arr[i];
    if (arr[i] > 0) p++;
    if (arr[i] < 0) n++;
  }
  if (p >= s)
    cout << 1;
  else if (n >= s)
    cout << -1;
  else
    cout << 0;
  return 0;
}
