#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int ar[n];
  for (int i = 0; i < n; i++) cin >> ar[i];
  int positive = 0, negative = 0;
  for (int i = 0; i < n; i++) {
    if (ar[i] > 0)
      positive++;
    else if (ar[i] < 0)
      negative++;
  }
  if (positive >= ((n + 1) / 2))
    cout << 1 << endl;
  else if (negative >= ((n + 1) / 2))
    cout << -1 << endl;
  else
    cout << 0 << endl;
  return 0;
}
