#include <bits/stdc++.h>
using namespace std;
int main() {
  int i, j, n, arr[1000000], pos = 0, neg = 0, temp, temp1;
  cin >> n;
  for (i = 0; i < n; i++) cin >> arr[i];
  sort(arr, arr + n);
  for (i = 0; i < n; i++) {
    if (arr[i] > 0)
      pos++;
    else if (arr[i] < 0)
      neg++;
  }
  if (n % 2 == 0)
    temp = n / 2;
  else
    temp = (n / 2) + 1;
  if (neg >= temp && pos >= temp)
    cout << (-1);
  else if (pos >= temp)
    cout << 1;
  else if (neg >= temp)
    cout << -1;
  else
    cout << 0;
  return 0;
}
