#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, dem1 = 0, dem2 = 0, dem3 = 0;
  scanf("%d", &n);
  int x = n / 2 + (n % 2);
  int a[n];
  for (int i = 0; i < n; i++) {
    scanf("%d", &a[i]);
  }
  for (int i = 0; i < n; i++) {
    if (a[i] > 0) dem1++;
    if (a[i] < 0) dem2++;
  }
  if (dem1 >= x) {
    printf("1");
  } else if (dem2 >= x) {
    printf("-1");
  } else {
    printf("0");
  }
}
