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.
Trivial map/filter reduce is not a novel kata idea, and there're also several katas where you have to use singular/plural based on the resulting number, so that's not new either.