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Subject: Re: One Reply Extension

Author: James Long

Date: 18:55:21 02/20/99

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On February 20, 1999 at 21:31:13, Nobuhiro Yoshimura wrote:

>I have a question for how other programmers are  implementing it.
>When we use iterative-deeping and transposition table, it is very likely
>to get a good move from a hash table.   Since we get the move without
>calling a move-generator and start searching, I have no idea whether or
>not the node has only one move.
>
>How do you know ?
>Do you call a special check routine in order to know the node has a sinlge move
>when king in check?

Hi Nobuhiro,

Before the null search, I set the pointer in the move stack
for <ply+1> to the pointer at <ply>.

After I get a move to search (which may be the move suggested
by the trans/ref table), I do a simple test to see if I'm
in check *and* first[ply+1] - first[ply] == 1.

If this is true, it's because the move generator was called
(otherwise they would still be equal).

I have no way of determining if the hash move was the *only*
reply.  Maybe you could store this information in the hash
table as well?

---
James




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