Nevermind my comment. It was a performance issue. I tried another approach and worked. This is what i like about code wars. Instead of making me just solve the problem anyhow, its actually making think of the "right/proper" solution. Amazing Kata.

Which language please? If it js, paste your code as a comment with spoiler tag and I will have a look.

I have exact same issue :( Not sure how to submit it. It passes all 60 random tests and just fails to submit saying performance issue.