[plt-scheme] HtDP newbie question, 12.4.2

From: Mark Engelberg (mark.engelberg at gmail.com)
Date: Fri Mar 28 18:04:03 EDT 2008

> Here are the tables with all of the values, as you suggested:
>
> First Table:
>
>    s   |   word  |   (first word)  |  (insert-in-single-word s (rest word))
> | expected result for (insert-... s low)
>
> --------------------------------------------------------------------------------------------------------
>    'X   |(list 'A 'T)|     'A          |  (list (list 'X 'T) (list 'T 'X)) |
> (list (list 'X 'A 'T) (list 'A 'X 'T) (list 'A 'T 'X))
>

This is where you were the closest.  In my opinion, you've been
getting further off track since then.
You need to figure out how to put together the pieces in the first
four columns, to get the thing in the final column.
Stay focused on that.  Matthias has given some strong hints, but
perhaps some of his comments are also confusing you.

So back to this chart... Can you articulate a strategy for putting
together the pieces from the first four columns to get the final
column?  Try describing the strategy in plain English.

If not, maybe you need to add a few more examples to this chart (try a
three-letter word, and a four-letter word), to see what patterns
emerge.

--Mark


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