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Re: Breakthrough

Message-ID <4FD2A643.6894@mindspring.com> (permalink)
Date 2012-06-08 21:26 -0400
From pete <pfiland@mindspring.com>
Organization PF
Newsgroups comp.lang.c
Subject Re: Breakthrough
References (4 earlier) <d2pts7lcahumia00egio0lh881b1trn9nc@4ax.com> <4FCF56CD.962@mindspring.com> <98pus75mg8q054gcv696u78gvg7gs6h1nk@4ax.com> <4FCFEC9A.C74@mindspring.com> <jqrdv0$p9f$1@speranza.aioe.org>

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jacob navia wrote:
 
> I am convinced my code would benefit from your critical eye Pete.
> 
> Just download it from
> 
> http://code.google.com/p/ccl/
> 
> and look at it.
> The file listgen.c contains the templated sort function.

The first mistake that I noticed, is a common one.

In 
    static void QSORT(LIST_ELEMENT **base, size_t num)
these two expressions
     COMPARE_EXPRESSION(loguy,lo) <= 0
     COMPARE_EXPRESSION(higuy,lo) >= 0
should be written this way
     COMPARE_EXPRESSION(loguy,lo) < 0
     COMPARE_EXPRESSION(higuy,lo) > 0
to properly address the issue of
     How to handle keys equal to the partitioning element?

See page 4 of
    http://www.cs.princeton.edu/~rs/talks/QuicksortIsOptimal.pdf
    How to handle keys equal to the partitioning element?
by Robert Sedgewick and Jon Bentley.

-- 
pete

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Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-04 13:38 +0200
  Re: Breakthrough MelissA <melis@a.com> - 2012-06-04 14:20 +0200
    Re: Breakthrough Juha Nieminen <nospam@thanks.invalid> - 2012-06-04 15:32 +0000
      Re: Breakthrough Ike Naar <ike@iceland.freeshell.org> - 2012-06-04 15:44 +0000
        Re: Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-04 18:03 +0200
          Re: Breakthrough Ian Collins <ian-news@hotmail.com> - 2012-06-05 10:23 +1200
            Re: Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-05 00:31 +0200
              Re: Breakthrough Luca Risolia <luca.risolia@studio.unibo.it> - 2012-06-05 01:43 +0200
                Re: Breakthrough Martin Shobe <martin.shobe@yahoo.com> - 2012-06-05 00:26 +0000
      Re: Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-04 17:47 +0200
        Re: Breakthrough Juha Nieminen <nospam@thanks.invalid> - 2012-06-05 05:36 +0000
      Re: Breakthrough Paul <nospam@needed.com> - 2012-06-04 12:32 -0400
      Re: Breakthrough MelissA <melis@a.com> - 2012-06-04 21:44 +0200
        Re: Breakthrough MelissA <melis@a.com> - 2012-06-04 22:01 +0200
          Re: Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-04 22:42 +0200
            Re: Breakthrough MelissA <melis@a.com> - 2012-06-05 00:16 +0200
              Re: Breakthrough MelissA <melis@a.com> - 2012-06-05 00:47 +0200
              Re: Breakthrough MelissA <melis@a.com> - 2012-06-05 03:34 +0200
      Re: Breakthrough 88888 Dihedral <dihedral88888@googlemail.com> - 2012-06-06 17:28 -0700
  Re: Breakthrough "BartC" <bc@freeuk.com> - 2012-06-04 17:30 +0100
    Re: Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-04 19:30 +0200
      Re: Breakthrough "BartC" <bc@freeuk.com> - 2012-06-04 19:18 +0100
        Re: Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-04 20:50 +0200
          Re: Breakthrough "BartC" <bc@freeuk.com> - 2012-06-05 00:31 +0100
  Re: Breakthrough pete <pfiland@mindspring.com> - 2012-06-04 17:23 -0400
    Re: Breakthrough Noob <root@localhost> - 2012-06-05 09:10 +0200
      Re: Breakthrough Ike Naar <ike@sverige.freeshell.org> - 2012-06-05 08:03 +0000
      Re: Breakthrough pete <pfiland@mindspring.com> - 2012-06-06 00:20 -0400
        Re: Breakthrough Robert Wessel <robertwessel2@yahoo.com> - 2012-06-06 00:06 -0500
          Re: Breakthrough pete <pfiland@mindspring.com> - 2012-06-06 09:10 -0400
            Re: Breakthrough Robert Wessel <robertwessel2@yahoo.com> - 2012-06-06 09:23 -0500
              Re: Breakthrough pete <pfiland@mindspring.com> - 2012-06-06 19:49 -0400
                Re: Breakthrough Willem <willem@toad.stack.nl> - 2012-06-07 15:10 +0000
                Re: Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-08 01:37 +0200
                Re: Breakthrough pete <pfiland@mindspring.com> - 2012-06-08 09:55 -0400
                Re: Breakthrough pete <pfiland@mindspring.com> - 2012-06-08 21:26 -0400
                Re: Breakthrough pete <pfiland@mindspring.com> - 2012-06-09 23:49 -0400
                Re: Breakthrough 88888 Dihedral <dihedral88888@googlemail.com> - 2012-06-11 06:50 -0700
                Re: Breakthrough pete <pfiland@mindspring.com> - 2012-06-11 22:36 -0400
  Re: Breakthrough Ian Collins <ian-news@hotmail.com> - 2012-06-05 10:02 +1200
    Re: Breakthrough jacob navia <jacob@spamsink.net> - 2012-06-05 00:26 +0200

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