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Subject: Re: If you want solve one mate...

Author: Pete Galati

Date: 16:39:16 01/21/01

Go up one level in this thread

On January 21, 2001 at 19:26:43, Paul wrote:

>On January 21, 2001 at 19:24:32, Pete Galati wrote:
>>On January 21, 2001 at 19:17:18, Paul wrote:
>>>On January 21, 2001 at 19:14:08, John Coffey wrote:
>>>>On January 21, 2001 at 16:56:42, Paul wrote:
>>>>>On January 21, 2001 at 11:56:09, leonid wrote:
>>>>>>This mate position is very handy when you want to check the limits in your
>>>>>>program. It is amusing also. Number of legal moves for both sides is slightly
>>>>>>over one hundred.
>>>>>> knq3q1/rq1q1qbQ/Qq2Q3/1Qn1Q2B/Q1qN1Q1r/4K1B1/1q4QR/1N1q3Q white to go.
>>>>>>If you will solve, it will be nice if you will indicate your result.
>>>>>Hi again Leonid!
>>>>>It took my program 45 minutes ... phewwwwwww!
>>>>>Here's the line, a mate in 12:
>>>>>1. Qxa7+ Qxa7 2. Qxa7+ Kxa7 3. Qeb6+ Ka8 4. Qgxb7+ Qdxb7 5. Qxb8+ Qxb8
>>>>>6. Qxb8+ Qxb8 7. Q6a5+ Na6 8. Qaxa6+ Qa7 9. Qg8+ Bf8 10. Qxf8+ Qe8+
>>>>>11. Qfxe8+ Qc8 12. Qxc8x
>>>>>I think I'm going to skip your next problem, that will be too difficult
>>>>>for me ;)
>>>>Fritz 6 has been thinking for 3 hours and 45 minutes, shows no analysis and
>>>>still says 1/1 ply.  I wonder what is happening with the transposition table,
>>>>John Coffey
>>>It's the QSearch blowing up, you have to control that somehow ...
>>>and that's easier when you're the author of the program in question :)
>>I'd try rebooting and try again.  Something sounds broken with searching on a
>>position for 3 hours and being at 1/1 ply.  That's just not right (Louie
>>Anderson impression).
>Well, I *was* waiting for your solutions from Comet & Junior ...
>or have you been rebooting al this time ;)

Oops, I must be becoming known for what I run analysis through, but I figure
everyone else will use Fritz and Crafty etc., so why should I?

Actually, I've been running Junior on that other position that you pasted in
that you said you gotta go deep to get an answer on, and Junior doesn't seem to
be coming up with anything (that I know of)

New position
5n2/B3K3/2p2Np1/4k3/7P/3bN1P1/2Prn1P1/1q6 w - - 0 1

Analysis by Junior 6.0:
1.Neg4+ Kf5 2.Nh6+ Ke5 3.Nf7+ Kf5 4.Nd6+ Ke5 5.Ng4+ Kd5 6.c4+ Bxc4 7.Ne3+ Ke5
8.Ndxc4+ Ke4 9.Nxd2+ Kd3 10.Nxb1
  +-  (4.74)   Depth: 20   00:17:19  573914kN
1.Neg4+ Kf5 2.Nh6+ Ke5 3.Nf7+ Kf5 4.Nd6+ Ke5 5.Ng4+ Kd5 6.c4+ Bxc4 7.Ne3+ Ke5
8.Ndxc4+ Ke4 9.Nxd2+ Kd3 10.Nxb1
  +-  (4.74)   Depth: 21   00:34:58  1156402kN
  +-  (5.04)   Depth: 22   00:53:15  1735924kN

(Galati, ` 21.01.2001)

But then I just saw that position after I made that post (you'd think I'd pay
more attention!!) and I can see why that position is giving programs brain
freeze.  There's just too many explosives in the stockade.


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