yes, noticed the mistake after submitting.

Never before has a comment been so correct. lol.

A range?
https://www.regular-expressions.info/charclass.html
I've only heard "character class". Though I do agree, a group and especially a "capture group" sounds like part of the match surrounded by parentheses.

not a group guys, if something is within brackets [] its called a range. a group would be chars surrounded by parenthesis e.g. (abcdef)

Nice one line solution, and an elegent use of ES6. Without running benchmarks, the top solution is probably much faster since this needs to create an anonomous function and convert between variable types a few times. +1 clever

be careful with this one. You named the paramater "array" which could be really confusing for anyone else looking at this, considering the function accepts strings.

Well done, but thats alot of code!

I love this site, but i think maybe people are too quick to upvote elegant looking code. In the workplace, consistancy and scalability count, not elegance or even being consise.

Base test should include an instance where the lowest numbers is a duplicate. I created a solution that passed all but one random test where this was the case.

This is probably best practice since it

1. preserves originial array
2. avoids the sort mechanic which will perform poorly if the array gets too large.

I wanted a solution like this, but it got too complicated for me. Nice work.

Wow, this looks incredibly streamlined.. nice use of ES6 functions.

This deserves clever and best practice. Boss tells you he wants to change the format, just manipulate the variable called "format"