you can just check if its exists...

check the array for contains undefined or null and return false?) as the description says?)

Glad to hear it, thanks, you too ;P

can agree only becous of node version 8.1 used in this kata otherwize 6 kuy its more then enough.

slowly re-read Kata's description and you got it.

i guess you already figured it, but i say for further guys who face with same problem, just slowly re-read the description of kata, and you can figure out why you failing one of basic tests.

so in general I did not see, there are certainly more elegant solutions, but apparently everyone had problems with "-".

i guess you dont need to check if s.length , since if you use .join('') on empty array you got empty string.

thanks for the info, yeah seem's mb for 2013 its was not so easy ;D

its not 5 kuy for sure, seen a lot of kata's 7 kuy harder then that. (at least need some perfomanse check tests, wich not allows the brute forсe solutions)

i guess for 2022 tests are so weak, and also yeah , its mostly feels like 6 or even 7 kyu.

Why you think so? i guess its mostly 6 kyu, or mb easyer then some 6 ...