That's not what the provided Node class looks like though is it? The description also says what an empty node is, and for the class you pasted it would not be created with Node() but with Node(None)

Regardless, the kata is in draft and looking dead, its test feedback is garbage, and its empty node concept smells - data structures really shouldn't be looking at the data. If they want a dummy node in front then ALL lists should have the dummy instead of looking at the data field. ...don't bother?

"works" in this context means that you your code didn't fail because you did not test the case that fails

if you're looking at the string the keyerror mentions, that's what you gave to a dict for lookup. you should be looking at what the input was instead.

it is defined though so uh how are you running this? locally?
... oh. you explicitly import preloaded in your solution. the idea with preloaded though is kinda that you don't need to import it. preloaded. already there.

The error is thrown in your code, check the stacktrace:
at Kata.solution(Kata.java:3)

string.split() treats its parameter as a regexp, so it is your code that could use Pattern.quote() ;-)

In what language?

Getting error from the tests themselves,

Unmatched closing ')' near index 1 :-)

If I'm not mistaken just using Pattern.quote() around the Strings that contain parentheses should fix this.

js, rust: missing random tests (and as listed earlier, java, coffeescript .. maybe others too)

python: I can find incorrect solutions without scrolling far
https://www.codewars.com/kata/reviews/5463ab67541c67d9b0000064/groups/54646d6b1e0c08c2bf0005c3
https://www.codewars.com/kata/reviews/5463ab67541c67d9b0000064/groups/5464331c1e0c08c27300032f
https://www.codewars.com/kata/reviews/5463ab67541c67d9b0000064/groups/5cb16411a87081000133bdad
https://www.codewars.com/kata/reviews/5463ab67541c67d9b0000064/groups/6869fc192fce17443d23eca4
https://www.codewars.com/kata/reviews/5463ab67541c67d9b0000064/groups/6462877b58774100011545ce
that's even though it has "random" tests but they're not producing good cases, much less being thorough

scala likewise has trouble telling apart endswith and contains+last char eq

why isn't empty text tested? solution("", "") solution("", "a")

no

the issue tag is used to keep track of changes that need to be done to a kata. if you've identified something like that then please describe it a reasonably direct way so that others can easily see what you see without having to do several steps of reasoning before understanding what the problem is.

That's my point. I'm not interested in trying because I don't know what I need to accomplish. Maybe the problem is interesting. The kata isn't.

Input size is part of WHAT the problem is. If I have a thought on how I want to solve something, then I want to be able to reason about whether it is good enough to try.

Some people will know exactly what algorithm(s) you are fishing for. If you don't specify input size, then you are catering only to those that will trivially solve it. For the rest, the experience is likely to suck.

Sadly, Discord is blocked for me anyway, and I can't use it, but I think I'm just going to start creating kata with something easier like this, but more interesting.
Edit: But I can use Github instead.

If you ask your parents, with your use case, they might surprise you. ( and then you may have to surprise yourself, and not get lost in other servers than Codewars .. )

Discord would really help you. Tell your parents I sent you.

I think using Discord would help me a lot, but it's blocked in my school, and my parents probably won't let me use it. But I can still learn from other kata, and other people.