A CP Solution for XKCD NP Complete Restaurant Order

Re:A CP Solution for XKCD NP Complete Restaurant Order by lake99 on Tuesday May 28, 2013 @09:39AM (#5779929)

Of course, Prolog makes it easy too.

    ?- member(Fruit,[0,1,2,3,4,5,6,7]),
       member(Fries,[0,1,2,3,4,5,6,7]),
       member(Salad,[0,1,2,3,4,5]),
       member(Wings,[0,1,2,3,4]),
       member(Sticks,[0,1,2,3]),
       member(Sampler,[0,1,2]),
       1505 is Fruit*215 + Fries*275 + Salad*335 + Wings*355 + Sticks*420 + Sampler*580.
       Fruit = Sampler, Sampler = 1,
       Fries = Salad, Salad = Sticks, Sticks = 0,
       Wings = 2 ; % << END OF ANSWER #1
       Fruit = 7,
       Fries = Salad, Salad = Wings, Wings = Sticks, Sticks = Sampler, Sampler = 0 ; % << END OF ANSWER #2
       false.

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Re:A CP Solution for XKCD NP Complete Restaurant Order by maaaats on Tuesday May 28, 2013 @10:32AM (#5780251)

As a person not heavily invested in Prolog, can you explain how that works? Is it just branching by choices from the different groups and it backtracks/fails back up to the last choice if constraints are not met?

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Re:A CP Solution for XKCD NP Complete Restaurant Order by kaoD on Tuesday May 28, 2013 @10:57AM (#5780393)

Pretty much that, yeah.

http://en.wikipedia.org/wiki/Unification_%28computer_science...

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