[plt-scheme] Scheme Programming Question (Making an error message)

Shriram wrote:

> PS: What I'd really like to know is what crackpot professor put out
>     a question like this.  Any ideas?

The basic concept of the question is fine, though it could be phrased 
much better (clearly the author has not heard of HtDP). But regardless 
of any infelicities, I'm sure the author would be interested in knowing 
the ways in which their students are attempting to solve the question... 
--PR