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.
Please provide an example of such cases in another comment, but this is impossible with the number of solutions in JS. Also, seems like you've passed the kata, closing!!!
It does not seem performant. I tested this against some of the other top solutions and it gets ~ 7s performance time vs ~2s performance time for other solns.
In what language
That requires a higher Node's version to work: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/flat#browser_compatibility