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From: Tucker Taft <stt@avercom.net>
Newsgroups: comp.lang.ada
Subject: Re: Programming Contest
Date: Sun, 22 Jul 2001 21:26:38 -0400
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Al Christians wrote:

>
> It looks to me like this is a problem of searching a huge search
> space for a good solution.  Anyone have any idea if there is any
> non-brute-force way to construct or find the solutions?

This looks like a problem ripe for "dynamic programming" solution.

>
> Has anyone in this group used Ada to solve such problems?   Any
> features of Ada that made it particularly well-suited?

Dynamic programming can be implemented in almost any language.

>
>
> I'm guessing that Lisp and similar languages might be better for
> writing a program,

Actually, probably most dynamic programming systems are programmed
in Fortran!  In any case, in this kind of system, I don't think Lisp has
anything over Ada.  The place where a language like Lisp shines is where
you actually want to manipulate bits of program within the language itself.
This problem seems like one which just needs a good data structure to support
the dynamic programming solution.  Basically, you start with a very simple
problem,
solve that by a smple search, and then build up solutions of more complicated
problems using results saved away for solutions to smaller problems.

> but that Ada would run a little faster so you
> could search more in a given time.  In particular, Ada is probably
> much better at pulling a slice out of a list (array) than most of
> the functional languages, and this might make Ada much faster at
> generating and evaluating solutions.
>
> Any ideas what would work best -- genetic algorithm, simulated
> annealing, or ???

As mentioned above -- dynamic programming.


>
>
> Al

-Tucker Taft  stt@avercom.net