wow. that's 39 bytes, when minified.

!TypeError: Cannot read properties of undefined (reading 'How')

Check the details section:
"For calculating the average point you may add your point to the given array!"
To my understanding that adding yourPoints is optional

not work

I remembered that regexes exist but not replace. How.

Would it be better to use '' than None?

Missing yourPoints as part of the average...

so good comment!

yes, i agre with you!

good job

Should be fixed after 6 years ~~

Looks clever but in terms of cost:

• you have to scan the string many, many times

• each time you do parens.replace you are generating a new string.

Short and sweet!

Empty array dosen't have damaged

This is irrelevant. We are interested in undamaged arrows, it doesn't matter if there are damaged ones and it isn't checked.

Thats beautiful, but I don't understand how it passess empty array test. What should I read about to fully understand that solution?
I read it as: "Return true, if some of 'a' dosen't have 'damaged' value. " Empty array dosen't have damaged, so why isn't it truthy?