From: Ryan Leavengood <leavengood@...>
Date: 2005-11-22T02:38:16+09:00
Subject: Re: [QUIZ SOLUTION] Euchre Hands (#55)

On 11/21/05, David Balmain <dbalmain.ml@gmail.com> wrote:
> Got to get back to work. 166 chars;
> a=$<.readlines;s='dchs';c='AKQJT9';t=a.shift;u=(t[0]+32).chr;i=s.index(u);v=s[i-2].chr;puts
> t,a.sort_by{|k|(k=~/J[#{u+v}]/?0:50)+(s.index(k[1])-i)%4*10+c.index(k[0])}

Brilliant. I'm extremely impressed. I learned quite a bit from it too,
which is one of the reasons I like code golfing so much. Plus it is
fun and rather addictive, as you have learned.

For those wondering, here is what I learned from David's changes to my code:

1. The extra newlines don't need to be cleaned out from the input
since "puts" seems to ignore them.
2. For compactness it is better to use strings rather than %w{} arrays.
3. Ruby's array and string indexing already takes care of
"wrap-around" when indexing since negative indexes work. So given a
string s of length 4, s[(i+2)%4] and s[i-2] are equivalent for values
of i from 0 to 5.
4. You can get the index of either a string or a fixnum representing a
character using String#index.
5. Using % on a negative number yields a positive number, which is
cleverly used above in calculating the weight. My math is rusty I
guess, or in fact, I'm not sure I ever learned what performing modulus
on a negative number is supposed to return. But I Googled it and
learned now.

But there is a problem in my code (both the above and the longer
version) which I just noticed (and that Zed brought up earlier): if a
suit is missing in certain cases the suits are not interlaced
properly. I'm wondering if I will bother going back to the drawing
board or not :)

Ryan