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From: tvmyers@koicds01.icdc.delcoelect.com (Thomas V. Myers)
Subject: Re: Help ! maze solving
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Date: Fri, 2 Dec 1994 01:47:32 GMT
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Jeff Smith (smithjj@s) wrote:
> In article <3avqkb$i1n@news.acns.nwu.edu>, agb669@lulu.acns.nwu.edu (Andrew G Bachmann) writes:
> |> If you are interested in the boring humdrum solution, you can always just set
> |> the robot to "keep it's hand on the wall".  It doesn't matter which wall you
> |> stick to.  Eventually the robot will get out of the maze.  This wouldn't be
> |> the "coolest" algorithm though, and I'm unqualified, (ie I don't know it), to
> |> give you one of those.
> |> 
> |> -Andrew Bachmann
> Andrew,

> You are correct as long as the maze does not contain "islands" that is,
> two paths to the same location.  I always make my mazes with islands to
> defeat this alogrithm.  Another algorithm I use is to start at the 
> finish and work backword.  I try to defeat this solution technique by
> building the maze in both directions toward the middle.

> Jeff Smith

I have to disagree with you Jeff.  The 'hand-on-the-wall' algorithm cannot be
defeated by islands because the 'hand' will never encounter an island, only
the walls opposite the walls of them.  It can only be defeated if the maze
has multiple exits and you want to find a particular one that is not the
first encountered in the direction you start the search.  Perhaps you were
talking about mazes where the goal is not an exit?

--
Tom Myers : tvmyers@icdc.delcoelect.com
