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Subject: Re: retrieving the PV from hash questions

Author: Robert Hyatt

Date: 19:41:32 09/06/04

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On September 06, 2004 at 22:05:58, Stuart Cracraft wrote:

>On September 06, 2004 at 18:33:47, Robert Hyatt wrote:
>
>>On September 06, 2004 at 04:47:12, Alessandro Scotti wrote:
>>
>>>On September 05, 2004 at 22:12:35, Stuart Cracraft wrote:
>>>
>>>>I walk the PV until there is no further position. No limit. This can then
>>>>either be left in the hash table if you don't clear between searches
>>>>but like Bob, you should keep the PV entries and restore them in the
>>>>hash table before the next search whether or not you table-clear due to
>>>>potential changes.
>>>>
>>>>I don't do this. It's a simple fix. I don't know why I've delayed putting
>>>>it in.
>>>
>>>I don't either. But since I get my PV from the hash table, it's already there.
>>
>>
>>It won't _always_ be there .  That is the problem.  You can overwrite a key
>>position and lose a move in the PV, and hence the _rest_ of the PV will not be
>>useful.
>
>I understand that. But unless you record the PV with an alternate technique,
>you can't fill it since source == destination.

I was assuming a non-flawed method of maintaining the PV.  :)



>
>And I am not sure I want to do the triangular array gubbish.


That's _the_ answer to do it right, however.  And it is trivial to do.




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