Loading collection data...
Collections are a way for you to organize kata so that you can create your own training routines. Every collection you create is public and automatically sharable with other warriors. After you have added a few kata to a collection you and others can train on the kata contained within the collection.
Get started now by creating a new collection.
I think you might be running the example testcases tab when there are no example testcases. Press the "Attempt" button which will run automated testcases. Your code perfectly for me. If it's a Codewars error, refresh and resubmit.