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