you mean 'teaches?'

That's exactly the contrary : it learns you how to debug !

Except in roguelike games.

Thanks!

which passed, but should not be the great of a performance gain

Well, it was significant enough so the tests passed :P O(n) vs O(n^2) is quite significant TBH...

Whether it is the author or the test server is irrelevent.

I'm confident it's the author's decision to forbid solutions with multiple loops, otherwise it could even be 8kyu. I can see the argument it could be 6kyu with perfomance constraints, but other users voted for 7kyu and it got approved as 7kyu (author can't change it). Also, there are many other katas, even 7kyu where simple approach will time out, on purpose, so downvoting based on that reason seems a bit unfair. (but you're entitled to that opinion)

Kata timed out for simple list comprehension.

But isn't that what you just did, and passed??

Should be able to apply simple list comprehension for a 7kyu and not expect performance hits. Rate a None for satisfaction.

That's a pretty BS reason for something that the author can't control.

Fair enough. I've added a non-integer sample test to the Javascript and Python translations to avoid any doubt on that point. In the other (statically typed) languages, it's already clear that the coordinates needn't be integral.

Reasonable...

Approved katas aren't gonna change, for the most part.