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