#include <bits/stdc++.h>
using namespace std;
const int N = 2e6 + 44;
const int dx[] = {1, 0, -1, 0};
const int dy[] = {0, 1, 0, -1};
const int mod = 1e9 + 7;
const int INF = INT_MAX;
int main() {
  ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  int n, ne = 0, po = 0;
  cin >> n;
  for (int i = int(0); i < int(n); i++) {
    int a;
    cin >> a;
    if (a > 0)
      po++;
    else if (a < 0)
      ne++;
  }
  n = n / 2 + n % 2;
  if (ne >= n) {
    cout << "-1";
    return 0;
  }
  if (po >= n)
    cout << "1";
  else
    cout << "0";
}
