Author: Dieter Buerssner
Date: 15:10:36 05/19/04
Go up one level in this thread
On May 18, 2004 at 13:23:24, Eduard Nemeth wrote:
>8/3k3p/1p4p1/p2p1p2/PP1K1P1P/2P3P1/8/8 b - - 0 1
>
>b6-b5! wins.
>
>Line:
>
>40... b5!! 41. Kxd5 axb4 42. cxb4 bxa4 43. Kc4 Kc6 44.
>b5+ Kb6 45. Kb4 a3 46. Kxa3 Kxb5 47. Kb3 Kc5 48. Kc3 Kd5 49. Kd3 h6 50. Ke2 Ke4
>51. Kf2 Kd3 52. Kf3 Kd2 53. Kf2 h5 54. Kg1 Ke1 55. Kg2 Ke2 56. Kg1 Kf3 57. Kh2
>Kf2 58. Kh3 Kg1! -+
>
>Which Program can find the winning move 40…b5!! and with a score >+1 for black?
I showed some analysis of Yace already. Now with the help of analysing
backwards. In the root position, I get:
8/3k3p/1p4p1/p2p1p2/PP1K1P1P/2P3P1/8/8 b - -
Engine: Yace 0.99.86 bb (200 MB)
by Dieter Buerssner
8/22 0:00 +8.45 1...b5 2.axb5 a4 3.c4 a3 (478.481) 873
8/26 0:01 +8.45 1...b5 2.axb5 a4 3.c4 a3 (1.616.162) 898
9/26 0:01 +8.45 1...b5 2.axb5 a4 3.c4 a3 (1.616.163) 898
9/30 0:06 +8.45 1...b5 2.axb5 a4 3.c4 a3 (5.662.774) 903
10/30 0:06 +8.45 1...b5 2.axb5 a4 3.c4 a3 (5.662.775) 903
The line shown may look stupid (especially the defence of white). The reason is,
that in the normal main line, already a mate or a very good score was seen (with
the help of the backward analysis). For example after 45...a3 46. Kxa3 in your
line, I got:
8/7p/1k4p1/1P3p2/5P1P/K5P1/8/8 b - -
Engine: Yace 0.99.86 bb (200 MB)
by Dieter Buerssner
14/01 0:00 +M32 7...Kxb5 8.Kb3 Kc5 9.Kc3 Kd5 10.Kd3 h6
11.Ke3 Kc4 12.Ke2 Kc3 13.Kf3 Kd2 (126) 1
This really is difficult (for my engine without backwards analysis). I have some
ideas, and perhaps soon this will be solved with convincing score fast.
After 44...bxa4, it is already much easier. Then I get (without backwards
analysis, and counting from move 1 again):
64709631 1:49.9 -1.61 17. 1.Kc4 Kc6 2.b5+ Kb6 3.Kb4 a3 4.Kxa3 Kxb5 5.Kb3
Kc5 6.Kc3 Kd5 7.Kd3 h6 8.Ke3 Kc4 9.Ke2 Kd5
10.Kf2 Kd6 11.Ke2 Kc7 12.Ke3 Kd7 13.Kf3 Ke8
14.Ke3 Kf7 15.Kd3 h5 16.Ke3 Ke6 17.Ke2 Kf7
18.Kd2 Kg7 19.Kc3 Kg8 20.Kb2 Kh8 21.Ka2 g5
22.fxg5 Kg7 23.g6 Kg8 24.Ka3 Kg7 25.Ka4 Kf6
26.Kb4 Ke7 27.Kb5 Kd8 28.Kc4 Kc7 29.g7 f4
30.g8=Q fxg3
72717539 2:00.3 -2.01 18-- 1.Kc4 Kc6 2.b5+ Kb6 3.Kb4 a3 4.Kxa3 Kxb5 5.Kb3
Kc5 6.Kc3 Kd5 7.Kd3 h6 8.Ke3 Kc4 9.h5 gxh5
10.g4 fxg4 11.f5 Kd5 12.Kd3 h4 13.f6 Kd6 14.Kc3
g3 15.f7 Ke7 16.Kd3 g2 17.f8=R g1=Q 18.Rf1
{-661}
93519671 2:25.7 -3.01 18-- 1.Kc4 Kc6 2.b5+ Kb6 3.Kb4 a3 4.Kxa3 Kxb5 5.Kb3
Kc5 6.Kc3 Kd5 7.Kd3 h6 8.Ke3 Kc4 9.h5 gxh5
10.g4 fxg4 11.f5 Kd5 12.Kd3 h4 13.f6 Kd6 14.Kc3
g3 15.f7 Ke7 16.Kd3 g2 17.f8=R g1=Q 18.Rf1
{-661}
129562985 3:08.1 -7.42 18t 1.Kc4 Kc6 2.b5+ Kb6 3.Kb4 a3 4.Kxa3 Kxb5 5.Kb3
Kc5 6.Kc3 Kd5 7.Kd3 h6 8.Ke3 Kc4 9.Kf3 Kd4
10.Kf2 Kd3 11.Kf3 h5 12.Kf2 Kd2H 13.Kf3H Ke1H
14.Ke3H Kf1H 15.Kd4H Kf2H 16.g4H fxg4H 17.Ke5H
g3H 18.Kf6H g2H 19.Kxg6H g1=Q+H 20.Kxh5H Kf3H
21.f5H {-841}
168302012 3:55.1 -7.42 18. 1.Kc4 Kc6 2.b5+ Kb6 3.Kb4 a3 4.Kxa3 Kxb5 5.Kb3
Kc5 6.Kc3 Kd5 7.Kd3 h6 8.Ke3 Kc4 9.Kf3 Kd4
10.Kf2 Kd3 11.Kf3 h5 12.Kf2 Kd2 13.Kf3 Ke1
14.Ke3 Kf1 15.Kd4 Kf2 16.g4 fxg4 17.Ke5 g3
18.Kf6 g2 19.Kxg6 g1=Q+ 20.Kxh5 Kf3 21.f5 {-841}
177354902 4:07.8 -7.82 19-- 1.Kc4 Kc6 2.b5+ Kb6 3.Kb4 a3 4.Kxa3 Kxb5 5.Kb3
Kc5 6.Kc3 Kd5 7.Kd3 h6 8.Ke3 Kc4 9.Kf3 Kd4
10.Kg2 Ke3 11.Kh1 Kf2 12.g4 fxg4 13.Kh2 g3+
14.Kh3 g2 15.f5 g1=Q 16.fxg6
This time I used "console mode" of the engine, therfore the different formating.
Cheers,
Dieter
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