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Date: Sun, 29 Mar 2015 21:54:04 +1100
Subject: Re: Sudoku solver
From: Chris Angelico <rosuav@gmail.com>
Cc: "python-list@python.org" <python-list@python.org>
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On Sun, Mar 29, 2015 at 9:35 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> Anyway, we don't really know where the confusion lies. Perhaps the
> description is misleading, or I'm just confused, or Bart's idea of brute
> force is not the same as my idea of brute force, or perhaps he really is a
> super-genius who has casually relegated C to the dust bin of historic
> languages...

Ah, I see what you mean.

I tend to describe an algorithm as "brute force" even if it has a few
simplifications and early cut-offs. A brute-force primality test, for
instance, might divide the target number by every counting number
since 1, looking for a remainder; does it cease to be brute-force if
you check only 2 and odd numbers? only those up to its square root?
Either of those tiny optimizations will give a dramatic speed
improvement, without representing a flaw; and I would still consider
them brute force. The purest form is a barbarian trying to lift a
gate; the slightly-optimized is a wizard trying to lift the same gate;
but neither algorithm is using a Knock spell to open it by magic. And
if you've seen "The Gamers", you'll know that brute force is as fickle
as a roll of the dice.....

Point is, "brute force" isn't a pure absolute from which there can be
no variation.

ChrisA