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Subject: Re: EGTB algoritmic question

Author: Dieter Buerssner

Date: 10:48:45 07/24/02

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On July 24, 2002 at 13:34:54, Alvaro Jose Povoa Cardoso wrote:

>Hi all,
>I've been working on EGTB generation with DTM.
>I use the 2 most significant bits of a byte to store win/draw/loss/broken.
>So I have 6 bits left for DTM that gives only 64 values wich are insufficient
>for my needs.
>My question is if there is a way to increase this 64 DTM limit and still use a
>single byte for each EGTB entry.

Sure, there is. By using one high bit for broken and loss, you lose lots of
space in the low bits. So and obvious scheme, that has DTM/draw/broken, could
use just 2 values for loss and broken. This leaves 254 values in a byte for the
mates. These values could be mated/mated in 1/mated in 2/.../mated in 126/mate
in 1/mate in 2/mate in 127. Actually, I think this (or very similar) is what
Nalimov TBs do. One could easily get rid of broken and mated (in 0), when one
has a trusted caller, which would give just one distance to mate more

Regards,
Dieter



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