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<DIV dir=ltr align=left><SPAN class=583190121-28082011><FONT color=#0000ff
size=2 face=Arial>I would like to add the following: by putting (wrong or
correct) solutions on a public list you do much harm to HtDP. It is essential
that readers of HtDP follow the instructions of the book. Giving someone else
the opportunity to copy/paste a solution of a problem does great harm to the
HtDP and may waste years of efforts put into HtDP. When I got access to the
solutions of HtDP exercises, I was strictly instructed (and rightly so) to not
reveal any substantial material on public forums, just for this reason. Leaning
is hard labour, I know, but you can't really learn by copy/paste. Rather on the
contrary. You can only learn by solving problems by yourself. Please do not
seduce other HtDP readers to quickly pass over an exercise without doing their
own homework. And if you get to a point where you can't proceed, many people are
willing to help you, provded you do so privately or by asking questions that do
not reveal (potential) solutions.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=583190121-28082011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=583190121-28082011><FONT color=#0000ff
size=2 face=Arial>Jos</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=583190121-28082011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=583190121-28082011><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV><BR>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B> users-bounces@racket-lang.org
[mailto:users-bounces@racket-lang.org] <B>On Behalf Of </B>Jos
Koot<BR><B>Sent:</B> domingo, 28 de agosto de 2011 22:48<BR><B>To:</B> 'cloud
van der Merwe'<BR><B>Cc:</B> users@racket-lang.org; 'Matthias
Felleisen'<BR><B>Subject:</B> Re: [racket] HTDP exersise
12.4.2<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV dir=ltr align=left><SPAN class=704113720-28082011><FONT color=#0000ff
size=2 face=Arial>I second Matthias. If in furture you have such questions, mail
them privately to someone you know who may have an answer. And if you don't have
someone like that send it privately to me if you like. I like teaching very much
and have much experience in teaching programming and also some experience with
helping HtDP students. I have access to the answers of HtDP problems, so I can
check that my answers are in line with the intentions of the author. I am
retired, but I cannot refrain from doing some teaching. Teaching is
not a job. It is a way of life.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=704113720-28082011><FONT color=#0000ff
size=2 face=Arial>Jos</FONT></SPAN></DIV><BR>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B> users-bounces@racket-lang.org
[mailto:users-bounces@racket-lang.org] <B>On Behalf Of </B>Matthias
Felleisen<BR><B>Sent:</B> domingo, 28 de agosto de 2011 22:25<BR><B>To:</B>
cloud van der Merwe<BR><B>Cc:</B> users@racket-lang.org<BR><B>Subject:</B> Re:
[racket] HTDP exersise 12.4.2<BR></FONT><BR></DIV>
<DIV></DIV><BR>
<DIV>
<DIV>On Aug 28, 2011, at 3:54 PM, cloud van der Merwe wrote:</DIV><BR
class=Apple-interchange-newline>
<BLOCKQUOTE type="cite"><SPAN
style="WIDOWS: 2; TEXT-TRANSFORM: none; TEXT-INDENT: 0px; LETTER-SPACING: normal; BORDER-COLLAPSE: separate; FONT: medium 'Lucida Grande'; WHITE-SPACE: normal; ORPHANS: 2; WORD-SPACING: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px"
class=Apple-style-span>Thanks guys, any criticism will be
appreciated!</SPAN></BLOCKQUOTE></DIV><BR>
<DIV>Please don't post complete solutions on-line. </DIV></BODY></HTML>