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From: nagle@netcom.com (John Nagle)
Subject: Re: 15-puzzle
Message-ID: <nagleD5CB7t.CJo@netcom.com>
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Date: Sun, 12 Mar 1995 18:26:16 GMT
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Igor Pechtchanski <ipechtch@its.brooklyn.cuny.edu> writes:
>Hi, everyone! I know this is a beginner's question, but that's what I am -
>a beginner. Does anyone have a good heuristic for a 15 puzzle or an
>algorithm?

    The usual approach is generally as follows:

	1.  Solve the top row.  Never touch it again.
	2.  Solve the left column. Never touch it again.
        3.  If the puzzle order is 2x2, you're done.
	4.  Recurse on the remaining subpuzzle.

					John Nagle
