<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">First, I'm working on problem: <a href="http://www.ccs.neu.edu/home/matthias/HtDP2e/part_two.html#%28part._sec%7E3apermute%29" class="bbc_url" title="External link" rel="nofollow external">How To Design Programs, 2nd Edition (Chapter 4, Section 4.5.1)</a>.   Second, I'm self-learning.   Now, I've made two attempts at this problem. <a href="http://pastebin.com/fxkNuh81" class="bbc_url" title="External link" rel="nofollow external">First</a> and <a href="http://pastebin.com/3DvDfNC9" class="bbc_url" title="External link" rel="nofollow external">Second</a>. My issue is that I know I'm doing something wrong. But I don't know what it is. My process of going through the problem is jacked somehow. In the first attempt, the code looks like right. I'm using recursion, following the steps the book has laid out (to the best of my understanding). But the result produced is the answer plus junk. In the second attempt, there is some recursion and helper functions. And the answers are correct. However, the code feels .... wrong. As if I didn't do it the Scheme way. It's like writing C with classes and not idiomatic C++. It works, but it's wrong.   So any tips, hints, pointing in the right direction, would be greatly appreciated.</td></tr></table>