#include <bits/stdc++.h>
using namespace std;
int n, p, np;
const int maxn = 1e2 + 100;
int a[maxn];
int main() {
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
    if (a[i] > 0) p++;
    if (a[i] < 0) np++;
  }
  if (p >= ((n + 1) / 2)) return cout << 1 << endl, 0;
  if (np >= ((n + 1) / 2)) return cout << -1 << endl, 0;
  return cout << 0 << endl, 0;
}
