#include <bits/stdc++.h>
int main() {
  int n, i, j, k, x = 0, y = 0, z = 0;
  int a[120];
  scanf("%d", &n);
  for (i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
    if (a[i] > 0)
      x++;
    else if (a[i] < 0)
      y++;
    else
      z++;
  }
  if (n % 2 == 0)
    k = n / 2;
  else
    k = (n / 2) + 1;
  if (x >= k)
    printf("1");
  else if (y >= k)
    printf("-1");
  else
    printf("0");
  return 0;
}
