Not a kata suggestion :)

sort mutates source.

So to avoid side effects, it must be copied before use.

Use spoiler flag please.

You need a more efficient solution.

Are the go tests adapted to be order agnostic? My tests were failing until I adjusted the code and changed the coordinates order.

I didn't think there would be, but that's good to know. Cool!

I did some benchmarking, did each 10,000,000 times several times, can't find any differences outside of the margin of error.

Thank you very much for your help. Now, I can apply that new trick to my future problems. Have a nice day. :)

try this: http://ruby-doc.org/core-2.2.0/String.html#method-i-5B-5D

Could somebody tell me where could I the explaination for this one in the Ruby API? Thanks in advance, and have a nice day.

I got the Ruby version to work but in Javascript, using .reduce takes too long with big numbers and site times out. Using a simple for loop results in incorrect math with higher numbers, and there's no way to import a bigint library.