Best in terms of function operating time. I mean, why do complex calculations when you can do it straight away? As a complete beginner, I discover on other katas that sometimes the simplest head-on solutions are the best in time, but sometimes complex calculations work tens of times faster than similar head-on solutions. I would also do it through a set so that the algorithmic time is O(1)

Can you please add to the description of the kata the condition that if n = 4 and m = 4? Or n or m is 3 and the other 4, it would be much clearer what to count

Thank you very much, now I understand the purpose of this kata

I don't understand this kata. Why 2013 is the first year after the old 1987 ? Okay, if we look from the point of view of the number 10: 1987 -- 2013:
1 is less than 2 by 1 ( 2-1 =1),
9 is less than 0 by 1 ((10+0)-9=1),
8 is less than 1 by 1 ((10-1)-8=1),
but 7 is not less than 3. It must be 6, ((10-7)-3=0, so it must be 1986.
So who is wrong, the author of the kata in the description of the kata or me?

I don't understand why this code and code from Voile works. I mean, I don’t understand why is this code suitable.

this binary or was cool, well done

It's very good code because it's fast, it's work ~1.04 sec on my comp and other's are mostly give 1.40 sec. Maybe this is the best code here.

What a fast code! 70 milliseconds on large number 73567465519280238573, others - ~ 28-30 second. The best code here no doubt

Very fast code here, just compare it on 73567465519280238573 number - works ~548 microseconds, others - 28-45 seconds, my god how beatiful!

x_middle school security team, I just see a man of culture))

ugly, but the fastest solution from all the solutions here (1.02 sec on my computer), others take >2 secs, here below there was a very beautiful and unusual solution, it works for 1.58 seconds but it is simply more worthy and I would use it.

When it comes to execution time, it's best variant out here. Молодец!