Here is the math behind every solution.
http://mathworld.wolfram.com/15Puzzle.html
Also, there are tons of these programs to download. I need some sleep, see you.
]]>Are they calling each state a node?
]]>That is the problem right there. I am not very good with graph theory. As a matter of fact, I stink.
]]>The algorithm isn't simple, it involves a lot of graph theory...
]]>Programming it, looks tough.
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