Yes. You can print the input as I suggested so you can see with which ones your code fails.

About [0,0,0]:

An array is said to be hollow if it contains 3 or more 0s in the middle that are preceded and followed by the same number of non-zero elements. Furthermore, all the zeroes in the array must be in the middle of the array.

• It contains 3 or more 0s
• All of them are in the middle of the array
• They are preceded and followed by the same number of non-zero elements (none in this case)

Is it clear now?

it is

what are you trying to achieve by getting the test cases ;)? if you are struggling to complete it, you can unlock solutions to see what other users have done

I'm considering the minimum length of the array to be 5.

That's not true.

Print the input to debug your code. What is a hollow array is well defined, not a kata issue, closing.

firstly, this is not an issue, this is a question, so try to post with question tag

secondly, you could try using markdown syntax to make the code more usable for ppl trying to copy/paste your code.

you can read this in the meantime

What? No :D It's your code. Just replace every print_r with return.

You are printing the result to console, when you should return it.