If the input array is empty or null, return an empty array.

if the number of positives = 0 (i.e no positive numbers) and sum of negatives = 0 (i.e no negative numbers), there are only two possible input arrays:

1. List consisting of zero's only, which has been covered in the example test cases

2. List is empty, which has been covered by

If the input array is empty or null, return an empty array

Sorry but you are wrong: 6/9 is 2/3 and 60 is divisible by 3.