Using the #sum method from Array is many, many times faster than using the alternative, inject or reduce.

I don't think the way CW is set up now that mass generating kata by simply altering minor features is productive. I agree it just dilutes the kata pool, and while useful for beginners, would quickly become frustrating even for them.

There should be a kind of alpha kata phase where people could not all the existing kata before someone goes to the work (which could be a lot for some) to write a kata only to get his with duplicate flags.

Or some kind of layered presenation and adjusted score so once you solve a kata the ones similar to it are hidden unless you manually search through them.

This is a trivial variation of all the existing integer to English words kata, e.g:

https://www.codewars.com/kata/wordify-an-integer
https://www.codewars.com/kata/integer-to-english
https://www.codewars.com/kata/ninety-nine-thousand-nine-hundred-ninety-nine
https://www.codewars.com/kata/counting-in-english-one-two-three-dot-dot-dot-to-2-quadrillion-2-000-000-000-000-000

So, a duplicate.

Needs random tests

Hi there, I'm not an expert in Ruby, but here you will find a very useful explanation on this matter.

https://blog.newrelic.com/2014/12/10/weird-ruby-2-rescue-interrupt-ensure/

Is it good to use rescue in ruby?

Clean and compact solution

Clean and readable solution

Good kata, thanks

Good kata, useful for practicing Matrix class in Ruby

Good kata, having in mind that this method returns a boolean, could be renamed to valid? according to best practices in ruby?

Thanks for this kata

Good kata for practising maths algorithms and ruby skills

Thanks, good kata for strings