Using count instead of size or length makes a huge difference: count traverses an Enumerable, so you're losing a lot of CPU time for nothing, especially on large collections.

http://batsov.com/articles/2014/02/17/the-elements-of-style-in-ruby-number-13-length-vs-size-vs-count/

That's not clever. Target was to output is as over-complicated as possible. Not as simple as possible.

OK, who's been marking this as 'clever'... ?

Oh, so I wasn't the only one with that solution. :D

Terrific kata! It took me a long time to understand the challenge and then about the same length of time to figure out how to solve it, but I felt I really learned something and I don't think I'd change anything. Kudos!!!

Nice kata and good tests. :-)

Ooos, I left debugging statement in there. Is there any way to delete a solution after submitting?

Glad to hear downvotes likely to go away and I agree that this is a nice community. :-)

When you say "user", do you mean the person developing the method to satisfy your written specification and your test? Or do you mean the person invoking the method?