# [plt-scheme] multiply-by-pi HTDP 11.5.2

I think you're forgetting the template (and, judging from the below you
maybe missed your contract & purpose). You're right that that approach
won't work, but maybe you can find another way to use your inputs.
Robby
At Tue, 20 Jun 2006 19:50:20 +0100, "wooks wooks" wrote:
>*
*>* http://www.htdp.org/2003-09-26/Book/curriculum-Z-H-15.html#node_sec_11.5
*>*
*>* I can only solve this problem by using + for the recursion. because my add
*>* function only works when at least one of the inputs is a natural number -
*>* i.e
*>*
*>* (define (add m n)
*>* (cond
*>* [(zero? n) m]
*>* [else (add1 (add m (sub1 n)))]
*>* )
*>* )
*>*
*>* which will obvious not work for the required recursion (add pi
*>* (multiply-by-pi (- n 1))).
*>*
*>*
*>* _________________________________________________
*>* For list-related administrative tasks:
*>* http://list.cs.brown.edu/mailman/listinfo/plt-scheme
*