#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, ans = 0, i, j, k, p = 0, q = 0, r;
  cin >> n;
  int a[n];
  if (n % 2 == 0) {
    r = n / 2;
  } else {
    r = n / 2 + 1;
  }
  for (i = 0; i < n; i++) {
    cin >> a[i];
    if (a[i] > 0) {
      p = p + 1;
    } else if (a[i] < 0) {
      q = q + 1;
    }
  }
  if (p >= q && p >= r) {
    cout << "5";
  } else if (q >= p && q >= r) {
    cout << "-5";
  } else {
    cout << "0";
  }
  return 0;
}
