#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int cases = 1;
  for (long long int i = 0; i <= cases - 1; i++) {
    long long int n;
    cin >> n;
    long long int a[n];
    for (long long int i = 0; i <= n - 1; i++) cin >> a[i];
    long long int c = 0, c2 = 0;
    for (long long int i = 0; i <= n - 1; i++) {
      if (a[i] > 0)
        c++;
      else if (a[i] < 0)
        c2++;
    }
    if (c >= (n / 2 + n % 2))
      cout << "1\n";
    else if (c2 >= (n / 2 + n % 2))
      cout << "-1\n";
    else
      cout << "0\n";
  }
  return 0;
}
