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Subject: Re: A bit of a confuser........

Author: John Merlino

Date: 20:55:58 07/24/02

Go up one level in this thread


On July 24, 2002 at 23:34:17, Slater Wold wrote:

>[D]1N4br/3pkPp1/6PP/8/pp3P2/8/P4r1P/6K1 w - - 0 1'
>
>Every program I tested found the correct move in about 5 seconds.
>
>Every program I tested then failed low for 10-13 ply.
>
>
>The real test here is not "finding" the move.  But finding that it's winning.
>
>How long does it take your program to find hxg7, and _know_ it's winning?

Chessmaster 9000 (PIII-600) finds the move instantly, and DOES fail low at ply
10. After that, the eval stays steady through to ply 13.

Time	Depth	Score	Positions	Moves
0:00	1/3	3.32	1973		1.hxg7 Rhxh2 2.f8=Q+ Ke6 3.Qxg8+
					Kd6
0:00	1/4	4.70	9531		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7
0:00	1/5	4.40	16406		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Kg3 Kxg7 6.Nxd7
0:01	1/6	4.40	74263		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Kg3 Kxg7 6.Nxd7
0:01	1/7	4.39	87914		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Nxd7 Kxg7 6.Kg3
					Kg6
0:02	2/8	4.42	124497		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Nxd7 Kxg7 6.Kg3
					b3
0:02	3/9	3.80	203060		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Nxd7 b3 6.Nf6
					Kxg7 7.Ne8+ Kg6
0:05	4/10	2.01	422430		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Nxd7 b3 6.axb3
					axb3 7.Ne5+ Kxg7 8.Nc4 Kf6
0:33	5/11	2.00	2574161		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Nxd7 b3 6.axb3
					axb3 7.Ne5+ Kxg7 8.Nc4 Kf6 9.Kg3
1:05	6/12	2.07	5089526		1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Nxd7 b3 6.axb3
					axb3 7.Ne5+ Kxg7 8.Nc4 Kf6 9.Kg3
					Ke6
3:04	7/13	2.03	14522913	1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2
					Bxf7 4.gxf7 Kxf7 5.Nxd7 b3 6.axb3
					axb3 7.Ne5+ Kxg7 8.Nc4 Kf6 9.Kg3
					Ke6 10.Nb2

HOWEVER, hxg7 still appears to lose anyway! After forcing CM9000's main line of
1.hxg7 Rg2+ 2.Kxg2 Rxh2+ 3.Kxh2 Bxf7 4.gxf7 Kxf7 (and you should agree that all
of White's moves are forced), we get this position:

[D]1N6/3p1kP1/8/8/pp3P2/8/P6K/8 w - - 0 5

And Chessmaster says this:

Time	Depth	Score	Positions	Moves
0:00	1/3	3.06	356		5.Kg3 b3 6.Nxd7 bxa2
0:00	1/3	4.38	392		5.Nxd7 Kxg7 6.Kg3 Kg6
0:00	1/4	4.41	945		5.Nxd7 Kxg7 6.Kg3 b3
0:00	1/5	3.77	4520		5.Nxd7 b3 6.Nf6 Kxg7 7.Ne8+ Kg6
0:00	2/6	2.00	11934		5.Nxd7 b3 6.axb3 axb3 7.Ne5+ Kxg7
					8.Nc4 Kf6
0:00	3/7	1.99	25482		5.Nxd7 b3 6.axb3 axb3 7.Ne5+ Kxg7
					8.Nc4 Kf6 9.Kg3
0:00	4/8	2.06	50786		5.Nxd7 b3 6.axb3 axb3 7.Ne5+ Kxg7
					8.Nc4 Kf6 9.Kg3 Ke6
0:00	5/9	2.01	99429		5.Nxd7 b3 6.axb3 axb3 7.Ne5+ Kxg7
					8.Nc4 Kf6 9.Kg3 Ke6 10.Nb2
0:02	6/10	-2.43	204435		5.Nxd7 b3 6.axb3 a3 7.b4 a2 8.b5
					a1=Q 9.b6 Qxg7 10.Kh3 Ke6
0:04	7/11	-3.32	479598		5.Nxd7 b3 6.axb3 a3 7.Nf6 Kxg7
					8.Ne8+ Kf8 9.Nd6 a2 10.b4 a1=Q
					11.b5 Qd4
0:07	8/12	-3.73	740137		5.Nxd7 b3 6.axb3 a3 7.Nf6 Kxg7
					8.Ne8+ Kf8 9.Nc7 a2 10.Ne6+ Ke7
					11.Nd4 a1=Q 12.Nc6+ Kd6 13.Ne5
0:13	9/13	-4.20	1263381		5.Nxd7 b3 6.axb3 a3 7.Nf6 Kxg7
					8.Ne8+ Kf8 9.Nf6 a2 10.Nh7+ Kg7
					11.Ng5 a1=Q 12.Ne6+ Kf6 13.Nc5 Qd4
0:24	10/14	-4.44	2318389		5.Nxd7 b3 6.axb3 a3 7.Nf6 Kxg7
					8.Nh5+ Kf8 9.f5 a2 10.Nf4 a1=Q
					11.Kh3 Qc3+ 12.Kg4 Kf7 13.Ne6 Qxb3
0:47	11/15	-4.52	4484987		5.Nxd7 b3 6.axb3 a3 7.g8=Q+ Kxg8
					8.Kh3 a2 9.Kg4 a1=Q 10.Ne5 Qd1+
					11.Kg5 Qxb3 12.f5 Qe3+ 13.Kf6 Qh6+
					14.Ng6 Qg7+ 15.Ke6 Qf7+ 16.Ke5
1:09	12/16	-4.60	6779430		5.Nxd7 b3 6.axb3 a3 7.g8=Q+ Kxg8
					8.Kh3 a2 9.Kg4 a1=Q 10.Ne5 Qd1+
					11.Kg5 Qxb3 12.f5 Qd5 13.Ng6 Qd2+
					14.Kf6 Qd6+ 15.Kg5 Kg7

Is CM9000 missing something?

jm



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