no problem, Ed. I don't know why you're passing one test but it doesn't lend any credibility to your approach; I hope you can re-work your algorithm to modify the input array "in-place"

oh for sure, I do know it's JS... it's just that (while not the case here) I keep hearing about all kinds of IDE's where we get the "it works on my machine" bit all the time, heh

@rowcased The language is JS, Big Boy doesn't exist.

it('Big boy is here', function () {

He's probably talking about that.

I don't know Big Boy, so I can only guess that your code only works there because Big Boy doesn't check the mutation of input, which your code does not handle.

you have to modify (mutate) the original array, so there is no point in declaring var a = []