[plt-scheme] How to change the following code to make it handle nested lists?

This reads like homework.  If you're doing the HtDP curriculum, the
answer is always "follow the design recipe".  If your course is not
following HtDP you might walk to talk to your instructor (or read
HtDP).

N.

On Mon, Nov 24, 2008 at 6:50 AM, SamuelXiao <foolsmart2005 at gmail.com> wrote:
> I have following code:
...
> It can handle the case summing up a list of numbers....however, I want
> to handle case like '(1 (2 3) 4), how can I make it?
> The code can handle (mysum '(1 2 3)) => 6, but when it comes to (mysum
> '(1 (2 3) 4))=>error.  Any help would be appreciated.