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