3 ms·

The puzzles are weird. Some of them could be a homework problem at a good elementary school (e.g. http://www.puzzlor.com/2012-10_FarmOR.html http://www.puzzlor.

by Pitarou 13y ago

The puzzles are weird. Some of them could be a homework problem at a good elementary school (e.g. http://www.puzzlor.com/2012-10_FarmOR.html http://www.puzzlor.com/2012-10_FarmOR.html). Others appear NP-hard, unless I'm mistaken (e.g. http://www.puzzlor.com/2013-06_SelfDrivingCars.html http://www.puzzlor.com/2013-06_SelfDrivingCars.html). Is the author trying to make a point about the nature of OR?

Jtsummers 13y ago
Re: Author's point - I don't think so. This seems like toy problems about how to frame problems in an OR style. Absorptive Markov chains (for the linked puzzle) are an OR tool that solves the problem very efficiently. Even though it's a small puzzle and it can be solved by hand with other approaches reasonably efficiently, those approaches may not scale as well to larger variations of the problem or aren't as general a solution or don't tie in as well when connecting a number of different optimization/planning problems. Regarding the wide-ranging difficulty of puzzles (perhaps it's just too late for me here, is that FarmOR one really an elementary school problem? EDIT: Just reread it, it's much easier than I originally thought because I misread it), it reminds me of the puzzles in CACM (I think it was that publication). They were generally math/CS puzzles, 3 at different levels of difficulty. The 3rd was - occasionally? often? - an open problem and all 3 would be similar, but different conditions (perhaps becoming more general) would increase the difficulty from puzzle to puzzle. On a given puzzle it might be trivial to solve 1 & 2 for a CS freshman, others might challenge seniors or grad students (depending on their domain at least). The author wasn't making a comment on the nature of CS, he (IIRC) was simply presenting puzzles and challenges. Some are easy, some are hard, some may be impossible without a lucky insight or domain familiarity.

by Pitarou 13y ago

Jtsummers 13y ago

Re: Author's point - I don't think so. This seems like toy problems about how to frame problems in an OR style. Absorptive Markov chains (for the linked puzzle) are an OR tool that solves the problem very efficiently. Even though it's a small puzzle and it can be solved by hand with other approaches reasonably efficiently, those approaches may not scale as well to larger variations of the problem or aren't as general a solution or don't tie in as well when connecting a number of different optimization/planning problems. Regarding the wide-ranging difficulty of puzzles (perhaps it's just too late for me here, is that FarmOR one really an elementary school problem? EDIT: Just reread it, it's much easier than I originally thought because I misread it), it reminds me of the puzzles in CACM (I think it was that publication). They were generally math/CS puzzles, 3 at different levels of difficulty. The 3rd was - occasionally? often? - an open problem and all 3 would be similar, but different conditions (perhaps becoming more general) would increase the difficulty from puzzle to puzzle. On a given puzzle it might be trivial to solve 1 & 2 for a CS freshman, others might challenge seniors or grad students (depending on their domain at least). The author wasn't making a comment on the nature of CS, he (IIRC) was simply presenting puzzles and challenges. Some are easy, some are hard, some may be impossible without a lucky insight or domain familiarity.