From: mathwft@math.canterbury.ac.nz (Bill Taylor)
Subject: Re: Bridges collapsing.  was: Problem with probability calculations.
Date: 31 Jan 2000 04:10:46 GMT
Newsgroups: sci.math
Summary: Bridg-It (game)

ikastan@uranus.uucp (Ilias Kastanas) writes:
 
|> 	One of Bill's .sigs says  "NZ graph theory is self-dual", or so...

Good memory there Ilias my main man!

|> suppose you are sailing down the river in
|> a tall ship, masts taller than bridge height; you'll get across iff a car
|> at one bank can _not_ cross to the other.

Yep, neat.  Clive or someone observed it was an example of the game Gale, 
also called Bridg-It.  One of the few games of some (former) worth that has
been completely solved, by human mind alone.  There are computer solutions
for lots of others, of course, mostly discovered by the inimitable Victor Allis,
but as the solutions are megalineful, and not wetware-codable, the games
survive as playable options.   Not so Bridg-It.   Pity.   There *are* ways
to resuscitate it, though perhaps a little artificial for everyone's taste.
That's more a topic for rec.games.abstract, however.

P.S.  I generally try to get my sig to have *something* at least allusively
      connected to my post, though I didn't use the one Ilias referred to
for the bridges problem, coz it would've given it away TOOO much.

Cheers all,

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*   *    *---*      N.Z. graph theory is...  SELF-COMPLEMENTARY !
|\  |       /    <---------------------------~~~~~~~~~~~~~~~~~~
| \ |      /        (Who else would compliment us...?)
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*   *    *---*      Bill Taylor        W.Taylor@math.canterbury.ac.nz
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