#include <bits/stdc++.h>
using namespace std;
void debug_out() { cerr << endl; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}
bool vowel(char c) {
  return c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u';
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  int s, p = 0, n = 0, d = 0;
  cin >> s;
  int a[s];
  int h = ((s - 1) / 2) + 1;
  for (int i = 0; i < int(s); i++) {
    cin >> a[i];
    if (a[i] > 0)
      p++;
    else if (a[i] < 0)
      n++;
  }
  if (p >= h) {
    d = 1;
  } else if (n >= h) {
    d = -1;
  }
  cout << d << endl;
  return 0;
}
