#include <bits/stdc++.h>
using namespace std;
int a[10005];
int main() {
  int n;
  scanf("%d", &n);
  int x1 = 0, x2 = 0;
  for (int i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
    if (a[i] < 0) x2++;
    if (a[i] > 0) x1++;
  }
  int t = n / 2;
  if (n & 1) t++;
  if (x1 >= t)
    puts("1");
  else if (x2 >= t)
    puts("-1");
  else
    puts("0");
  return 0;
}
