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From: buzzard@TheWorld.com (Sean T Barrett)
Subject: Re: Goal/Obstacle Puzzle Theory
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Date: Mon, 14 Jan 2002 23:43:12 GMT
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In article <772ca430.0201141525.4a74a00c@posting.google.com>,
>rcarbol@home.com (Roger Carbol) wrote in message
>It can almost be represented by a mathematical equation.
>A=(B+(C*D)-F(G/(H+I))-J)

You don't seem to have assigned any meaning to '+' versus
'*' versus '/', so I'll point out that this is just a way
of encoding what computer scientist people call a "tree"
(like the object tree in IF).

A tree is a subset of a class of data known as "graphs";
in general, IF puzzle chains form DAGs (directed acyclic
graphs, which trees are also a subset of). The obvious
sort of case here is where you have one puzzle dependent
on two others (G versus H&I) you can also have two puzzles
dependent on a single one, which cannot be notated as
an equation (although you could notate it by using multiple
equations).

Graham Nelson's DM4 has some charts like this.

SeanB
