That's what backtracking's for. :-)

Actually, that brings up an interesting question: Ovid, are there any bounds on how optimal the answer has to be? Exactly optimal (sucky if this problem turns out to be NP-Hard)? Within a constant factor of optimal (like, max length no more than 1.5x larger than optimal)?

--
The hell with paco, vote for Erudil!
:wq

In reply to Re(3): Puzzle: need a more general algorithm by FoxtrotUniform
in thread Puzzle: need a more general algorithm by Ovid

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