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Subject: Re: INFINIITY question

Author: Tony Werten

Date: 22:10:25 11/28/01

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On November 28, 2001 at 20:16:45, James Swafford wrote:

>On November 28, 2001 at 13:41:26, Tony Werten wrote:
>
>>On November 28, 2001 at 13:05:23, Derek Mauro wrote:
>>
>>>When I call search(), I'm supposed to be using -INFINITY as alpha and INFINITY
>>>as beta.  Anyway, I've never used INFINITY in a program before.  How do I use
>>>INFINIITY?  Do I need to include a special library or just define it as the
>>>largest possible int value, or something else?
>>
>>Just use the value you use for checkmate (without depth correction ) That's
>>infinite enough.
>>
>>Tony
>
>The absolute value for INFINITY for me is a little bigger than
>CHECKMATE, so that the condition  if (score > alpha) is true
>even when the first move gets a score -CHECKMATE and alpha is
>-INFINITY.  Nothing gets backed up to the pv unless that condition
>is met.  (Of course you're in serious trouble in that case. :)

You're already in trouble if a move scores -checkmate. If it happens at ply 0
than the game is finished, if it is ply 1 or more the score should be
-checkmate+1 (or more )

Tony

>
>
>--
>James



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