#include <bits/stdc++.h>
using namespace std;
int cnt1, cnt2, cnt3;
int main() {
  int n;
  cin >> n;
  int arr[n];
  for (int i = 0; i < n; i++) {
    cin >> arr[i];
    if (arr[i] > 0)
      cnt1++;
    else if (arr[i] < 0)
      cnt2++;
    else
      cnt3++;
  }
  if (n & 1) n++;
  n >>= 1;
  if (cnt1 >= n) {
    cout << 1;
  } else if (cnt2 >= n) {
    cout << -1;
  } else
    cout << 0;
}
