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Subject: Re: Question about Bit storage

Author: Dann Corbit

Date: 11:23:19 01/30/02

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On January 30, 2002 at 08:51:17, Vincent Diepeveen wrote:
[snip]
>all assumptions are of course wrong:
>
>  - EGTB ==> O(1) lookup, whereas in databases no such thing happens soon,
>    i miss a managed binary tree concept in your writings so you need O(n)
>    for every lookup AFAIK.

Unless you use hashing, in which case it is O(1)

>  - you waste bits. If you store a position you can better store the
>    hash like i do in my hashtable and then add a score to it. So you
>    would need 64 bits + 8 bits score at most. Side to move of course
>    doesn't need to get stored, nor bounds or whatever, nor best move,
>    waste of bits it is.

The format for the key is almost irrelevant.  It can be changed at any time.

>Most important is however that you do it all for nothing because:
>
>  - it will never save time putting your stuff in hashtable, but it will
>    instead waste memory as the the search space is just too big to store
>    in a few terabyte of memory, especially if you use 250 bits a position.

Amazing that you can know this before the experiment even takes place.  Who said
anyone was going to use 250 bits for a position?  It was just a demonstration of
the concept.  Apparently, you haven't quite got it yet.




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