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From: hall@aplcenmp.apl.jhu.edu (Marty Hall)
Subject: Re: Common LISP and Eight Queen problem
Message-ID: <DCFpIs.5A@aplcenmp.apl.jhu.edu>
Organization: JHU/APL AI Lab, Hopkins P/T CS Faculty
References: <whs.130.3018EABA@rau3.rau.ac.za>
Date: Fri, 28 Jul 1995 16:23:15 GMT
Lines: 15

In article <whs.130.3018EABA@rau3.rau.ac.za> whs@rau3.rau.ac.za (W.-H. Steeb) writes:
>I am looking for a Common LISP program
>which solve the eight queen problem.

Many people seem to be unaware that if all you want is ONE solution,
no search is required for solving N-Queens for *any* N >= 4, and the
location of the queen on each row can be calculated in constant time
per-row with just a few lines of code. The algorithm was given
SigArt Bulletin Vol 2 No 2, pg 7. 

I can send a Lisp implementation to anyone who is interested, but it
is just a straightforward implementation of the SigArg algorithm.

						- Marty
(proclaim '(inline skates))
