I like this solution.

I mean it's only a 6 kyu task and it has a regex tag, so it was kind of implied, that it should probably be solved with a simple regex.

$ sign wasn't even necessary.

Not actually a kata issue in this case, test cases are dependent on the year. I don't know why he designed it like that either though tbh.

Treating the whole array as a string is even better instead of iterating over it :)

Would have saved myself alot of time with this approach vs. writing a million if statements.

Yes, there's a difference. Your solution in fact more performant than the OP's solution. His solution has O(n^2) time complexity and yours is O(n) meaning it's much faster.

I tried to go this route, but I did not have in mind to merge the two like that.
Such a brilliant solution!

In python, I can pass the largest tests simply by returning zero. Furthermore, based on the error messages, it seems that the python reference solution is using floating point arithmetic, which cannot possibly work with the larger tests (perhaps this is why they are disabled?).

More of a logic problem than a coding challenge.

I think it's called numerical sequences in Math.

regex is amazing.

Same here, I couldn't figure out how to implement regex like this one then I gave up xD.

Nice!

I tried to go down this route, but couldn't figure out where to put the $ sign