#include <bits/stdc++.h>
using namespace std;
const long long MXN = 1e6 + 1;
const long long MOD = 1e9 + 7;
const long long INF = 1e18;
const long double EPS = 1e-9;
int64_t n;
int64_t cnt;
int64_t res;
signed main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  cin >> n;
  int64_t lol = (n + 1) / 2;
  while (n--) {
    int64_t x;
    cin >> x;
    if (x > 0) cnt++;
    if (x < 0) res++;
  }
  if (res >= lol) {
    cout << -1;
  } else if (cnt >= lol) {
    cout << 1;
  } else {
    cout << 0;
  }
  return 0;
}
