Re: [Shootout] Spellcheck.adb

[David Sauvage <pariakaman@gmail.com>]

Dmitry A. Kazakov wrote:
> ...
> The above is approximately five times faster on my computer under FC3.
> Probably, because it does not use hash tables?
> 

GNAT.Spitbol.Table generic use hash tables (i wonder if it could be 
called an hashed table maps method?), may be people would like to have a 
look on it's hash function (see #1)

The published shootout Ada spellcheck using GNAT.Spitbol.Table :
real    0m0.120s
user    0m0.083s
sys     0m0.007s

(i run all the programs several times before each post ;-), so i get 
fresh time average each post)

I try using the Tables generic package implementation (see #2) instead 
of GNAT.Spitbol.Table generic on the shootout Ada spellcheck 
implementation, which gave me  :
real    0m0.271s
user    0m0.197s
sys     0m0.014s

system configuration :
Debian GNU/Linux Sid - kernel 2.6.10 - 1.2 Ghz
gcc 3-3, GNAT 3.15p-12

#1 the GNAT.Spitbol.Table generic hash function
------------------------------------------------
(see g-spitbo.adb)
       function Hash (Str : String) return Unsigned_32 is
          Result : Unsigned_32 := Str'Length;
       begin
          for J in Str'Range loop
             Result := Rotate_Left (Result, 1) +
                       Unsigned_32 (Character'Pos (Str (J)));
          end loop;

          return Result;
       end Hash;

#2 The Tables generic package :
-------------------------------
(see previous post)
 > [ http://www.dmitry-kazakov.de/ada/tables.htm ]

David