in reply to Pairing Riddle (OT)

Given the down votes it attracted, it might have been better to motivate it with breeding dogs to avoid touching on taboos.° =)

But I enjoyed it from a mathematical perspective, since it's a a problem which can be perfectly described in graph theoretic terms: a directed graph with a "child of" relation with certain restrictions:

<Reveal this spoiler or all spoilers in this node or all in this thread>

Here the solution in short, but hidden behind a spoiler tag to protect those interested.

<Reveal this spoiler>

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

°) apparently do most so called "purebred" dogs have an inbreeding factor of 25%. That's like the outcome of incest. One more reason why I'd always opt for a mongrel.

¹) in some western countries this is technically legal, because the laws don't cover that case.

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Re^2: Pairing Riddle (OT)
by Ratazong (Monsignor) on Apr 27, 2026 at 07:49 UTC
    Hi LanX, there is another possibility not mentioned in your spoiler:
    <Reveal this spoiler or all in this thread>
    seems to be much easier than originally thought ... but does not involve any graph-theory ...

    So long, Rata

[reply]
      Thanks, Rata. But I think you missed the requirement in the OP that uncle/aunt by marriage doesn't count.

      > > > "Direct" means blood related, i.e sibling of one parent, not "uncle by marriage".

      In hindsight it becomes clearer why breeding dogs would be a better setting for this puzzle.

      Dogs don't know marriage, divorce and soap operas° ... ;)

      And many breeders rely on incest, restricting them to uncle/aunt relationships would be a "moral" advantage.

      Update

      The trivial solution (of many) if "by marriage" was allowed ...

      ... is to marry your fiancé*'s uncle/aunt first, like for a day:

      • Boy meets girl at a Perl conference and they discuss this puzzle
      • Both bring their cool nerdy uncle/aunt to the next YAPC in Las Vegas
      • They are cross-marrying the plus ones for a day, and hence are declared uncle and aunt by an Elvis impersonator at the pre conference meeting
      • They get divorced again by an Michael Jackson impersonator during the social event
      • They marry each other with the blessing of an Larry Wall impersonator during a lightning talk
      • The "marry my uncle first" tradition quickly becomes the cultural norm in silicon valley, after 25 years all other partnerships are declared illegal under the reign of emperor Peter Thiel.

      There is also a same gender marriage version of this riddle, but requires an orange Trump impersonator dressed as Dr. Jesus.

      Cheers Rolf
      (addicted to the Perl Programming Language :)
      see Wikisyntax for the Monastery

      °)

      <Reveal this spoiler or all spoilers in this node or all in this thread>

[reply]

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