#include <bits/stdc++.h>
class ABePositive {
 public:
  void solve(std::istream& in, std::ostream& out) {
    int n;
    int a[1005], neg, pos, zero, target;
    neg = pos = zero = 0;
    in >> n;
    for (int i = 0; i < n; i++) {
      in >> a[i];
      if (a[i] == 0)
        zero++;
      else if (a[i] > 0)
        pos++;
      else if (a[i] < 0)
        neg++;
    }
    target = ceil((double)n / (double)2);
    if ((n & 1 && zero >= target) || !(n & 1) && zero > target) {
      out << 0;
    } else if (pos >= target) {
      out << 1;
    } else if (neg >= target) {
      out << -1;
    } else {
      out << 0;
    }
  }
};
int main() {
  ABePositive solver;
  std::istream& in(std::cin);
  std::ostream& out(std::cout);
  solver.solve(in, out);
  return 0;
}
