Node 8.x JS does not have a stable sort. See other comments.

Yes, It is very idiot kata

You have an idiot bug in your solution. It handles upper case letters incorrectly, and does not maintain a proper order of letters.

As an added challenge, upper- and lowercase letters are considered the same character

G is repeated, it can't be the answer, the same for all letters and spaces until you reach the comma.

Go hang a salami, I'm a lasagna hog!

expected 'G' to equal ','

Yes, It is very idiot kata

Go hang a salami, I'm a lasagna hog!

expected 'G' to equal ','

Why?????

two loops is bad

If some sub sequences have the same sum value, sort them according to their original order.

I do not understand what is meant, I have all subarrays equal to 285 and therefore I did not change their sequence, but I have an error. Because they are in the wrong order. tell me about this exception

using a very fast code, with larger numbers I get not always the best option, but very approximate. Since the accuracy of the answer is important here, I decided to go through all the options, but with large numbers it takes a long time, as I expected. While I have an idea in my head to try the Algorithm with the division of the task into smaller tasks