As someone said, taking a look at the Primality Test in Wikipedia is REALLY helpful on this one.

Well, looks my comment was vastly misunderstood. I was just saying I was expecting a bit more of coding effort. Of course, Andi is 100% right and instead of using the library I could have started from scratch but we are supposed to get help from the ones who walked the same path before us, don't we?

I just read the description like 5 times and still don't get your idea of a worst case scenario. Obviously you need the sum of all the bribes in the worst case scenario which is that you guess the right door after attempting all the others first. But that doesn't involve any coding, so I'm back at square one totally clueless about what I'm supposed to do.

Great overall kata! Congrats! It was well explained with really good examples and it was challenging enough.

WOW!!!! I usually have very verbose code but yours is definitely off the charts. You should take a close look to the experienced guys' solutions and learn from there. And in this particular one, you're inventing the wheel when it's already invented long time ago. You are calculating the GCD from scratch and in not an efficient way instead of using the built-in function. Python comes with batteries included so take advantage of them!!!

Appreciate adding support for Python 3. Subtle changes but still necessary. Other than that, nice one.

Definitely too easy for 4kyu. Wording of the kata could be better but ok.

Nice kata! My compliments! My solution was so messy. Need to improve my recursivity.

Many complain about the description. It's not perfect but it's good enough. I've seen much worse. For the kata itself, it was kind of surprising to pass at the first attempt with quite a brute force approach. Was expecting a timeout.

The clue makes absolutely no sense to me and it's somehow impossible to give a more standard clue. I don't understand why. Really disappointed. It's a shame because your other katas were great.

10 minutes refreshing my calculus and doing the mathematical thing. 30 seconds coding it. It's more a calculus test rather than a coding one.

I like a lot the cipher katas. This was specially interesting because of the remember the spaces thing.

It's basically a brute force kata but you just have to apply the force on the right spot. Otherwise it gets timed out.

Very nice kata! It pushed my optimization skills to the limit. My solution was a bit sloppy and in the verge of the timeout but passed.

This kata is really easy for 5kyu