#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
const long long int LINF = 0x3f3f3f3f3f3f3f3fll;
int main() {
  int n;
  scanf("%d", &n);
  int pos = 0, neg = 0;
  for (int i = 0; i < n; i++) {
    int k;
    scanf("%d", &k);
    pos += k > 0;
    neg += k < 0;
  }
  if (pos >= (n + 1) / 2) return !printf("%d\n", 1);
  if (neg >= (n + 1) / 2) return !printf("%d\n", -1);
  printf("%d\n", 0);
  return 0;
}
