#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1e9 + 7;
int main() {
  long long n, cnt1 = 0, cnt2 = 0;
  cin >> n;
  for (int i = 0; i < n; i++) {
    long long a;
    cin >> a;
    if (a > 0) cnt1++;
    if (a < 0) cnt2++;
  }
  if (cnt1 >= (n + 1) / 2)
    cout << 1;
  else {
    if (cnt2 >= (n + 1) / 2)
      cout << -1;
    else
      cout << 0;
  }
}
