i agree. it kind of kills the point of this kata

@kjanus-thecreator Description says. "The tests contain some very huge arrays, so think about performance"
I insist this 6 kyu kata's solution should be implemented in imperative style, not two-lines declarative one. Otherwise it must be 7 kyu.

Says who? This is a perfectly functional soulution. No need to impose arbitrary limitations on ourselves

Thanks for the advice, beginner at codewars, haven't learned the local rules yet )

Thx. I believe it could be refactored even more, but have no time for this...
By the way, you may just press the buttons "Best Practices" and "Clever". Usually, comments are used to ask something or add some information.

Nice solution

In this kata, sorting is not appropriate.

getting better wont make up for piss poor explaination/description of problems

Nice solution!

Good kata!