Author: Uri Blass
Date: 16:24:19 08/21/02
Go up one level in this thread
On August 21, 2002 at 19:10:49, Vincent Diepeveen wrote: >On August 21, 2002 at 18:11:26, Uri Blass wrote: > >>[D]4r3/p2q2k1/2pp4/2p4b/QrP1P2b/1P1P1Pp1/P3N1R1/3RN2K w - - 0 36 bm Qa5 >> >>Questions: >>1)Is Qa5 winning? >>2)Is Qa5 the only win? > >this position is not interesting IMHO, usually engines make >way bigger mistakes than such ones. > >>I will be happy if somebody with fast hardware can analyze for some hours >>the possible alternatives Qa3 Qa5 and Qa6. >> >>Movei played Qa3 that is probably enough only for a draw >> >> >>[D]6k1/6r1/2Q3N1/2p5/2P1P1qb/1P1P2p1/P5R1/3b2K1 w - - 0 46 bm Qa8+ Qe8+ >>am Qd5+,Nxh4 >> >>Movei lost by Nxh4 > >I get draw score for Nxh4, also at bigger search depths. > >00:00 125 0k 0 0 5 (2) 1 (0,0) 0.455 Ng6xh4 Qg4xh4 Qc6xc5 >00:00 4800 5k 0 0 432 (2) 2 (0,7) 0.455 Ng6xh4 Qg4xh4 Qc6xc5 >00:00 8721 9k 0 0 1221 (2) 3 (0,43) 0.455 Ng6xh4 Qg4xh4 Qc6xc5 >00:00 23210 23k 0 0 4642 (2) 4 (1,85) 0.377 Ng6xh4 Qg4xh4 Qc6-c8 Kg8-h7 Qc8xc5 > >00:00 38323 38k 0 0 14946 (2) 5 (2,147) 0.527 Ng6xh4 Qg4xh4 Qc6xc5 Rg7-h7 Kg1- >f1 >00:00 58975 59k 0 0 38334 (2) 6 (5,221) 0.771 Ng6xh4 Qg4xh4 Qc6-c8 Kg8-f7 Qc8x >c5 Bd1-f3 Qc5-f5 Qh4-f6 Qf5xf6 Kf7xf6 >++ c6-d5 >00:00 58143 58k 0 0 45352 (2) 6 (5,239) 0.798 Qc6-d5 Kg8-h7 Ng6xh4 Qg4xh4 Qd5x >c5 Rg7-f7 d3-d4 >00:01 72993 73k 0 0 83942 (2) 7 (5,304) 0.001 Qc6-d5 Kg8-h7 Ng6xh4 Qg4xh4 Qd5x >c5 Rg7-f7 b3-b4 Qh4-f4 >++ g6-h4 >00:02 69057 69k 0 0 145711 (2) 7 (33,412) 0.350 Ng6xh4 Qg4xh4 Qc6xc5 Rg7-f7 Qc >5-b6 Qh4-f4 Qb6-g6 Rf7-g7 Qg6-e8 Kg8-h7 >00:03 81023 81k 0 0 279530 (2) 8 (53,576) 0.017 Ng6xh4 Qg4xh4 Qc6-c8 Kg8-h7 Qc >8xc5 Rg7-f7 b3-b4 Bd1-f3 Qc5-d5 >00:07 102641 103k 0 0 722596 (2) 9 (100,851) 0.001 Ng6xh4 Qg4xh4 Qc6-c8 Kg8-h7 Q >c8-f5 Kh7-g8 Qf5xc5 Rg7-f7 Qc5-b6 Qh4-f4 Qb6-d8 Rf7-f8 b3-b4 >00:11 127475 127k 0 0 1420078 (2) 10 (115,1099) 0.000 Ng6xh4 Qg4xh4 Qc6-c8 Kg8-h >7 Qc8-f5 Kh7-g8 Qf5-c8 >00:21 148919 149k 0 0 3148165 (2) 11 (132,1359) 0.000 Ng6xh4 Qg4xh4 Qc6-c8 Kg8-h >7 Qc8-f5 Kh7-g8 Qf5-c8 >00:34 160815 161k 0 0 5474162 (2) 12 (147,1673) 0.000 Ng6xh4 Qg4xh4 Qc6-c8 Kg8-h >7 Qc8-f5 Kh7-g8 Qf5-c8 >00:59 170556 171k 0 0 10062816 (2) 13 (173,2077) 0.000 Ng6xh4 Qg4xh4 Qc6-c8 Kg8- >h7 Qc8-f5 Kh7-g8 Qf5-c8 >02:12 174082 174k 0 0 23052044 (2) 14 (206,2599) 0.000 Ng6xh4 Qg4xh4 Qc6-c8 Kg8- >h7 Qc8-f5 Kh7-g8 Qf5-c8 In the game horizon did not play Kg8 but played Kh6 that seems to be a winning move. Finding it or not finding it like avoiding Nxh4 in the previous diagram is a question of evaluation. Crafty has no problem to do it because it evaluates black as better. Deep Fritz can find Kh6 but only with a very small score. When I analyzed the game by going backward I could convince yace that black has almost 1 pawn advantage. Movei 0.0.72h - Horizon 3.2 [D]8/6rk/8/2p2Q2/2P1P2q/1P1P2p1/P5R1/3b2K1 b - - 0 1 Analysis by Deep Fritz: 48...Kh7-g8-- = (0.03) Depth: 1/3 00:00:00 48...Kh7-g8-- 49.Qf5xc5 ² (0.31) Depth: 1/6 00:00:00 48...Kh7-g8 49.Qf5xc5 ² (0.31) Depth: 2/8 00:00:00 48...Kh7-g8 49.Qf5xc5 Bd1-f3 50.Qc5-d5+ Kg8-h7 = (0.25) Depth: 3/11 00:00:00 48...Rg7-g6! = (0.22) Depth: 3/11 00:00:00 1kN 48...Rg7-g6! 49.Qf5xc5 = (0.19) Depth: 3/11 00:00:00 1kN 48...Rg7-g6-- ² (0.50) Depth: 4/10 00:00:00 1kN 48...Rg7-g6-- ² (0.50) Depth: 4/14 00:00:00 2kN 48...Kh7-g8! ² (0.47) Depth: 4/14 00:00:00 2kN 48...Kh7-g8! 49.Qf5xc5 ² (0.44) Depth: 4/14 00:00:00 3kN 48...Kh7-g8 49.Qf5xc5 Rg7-h7 50.Qc5-c8+ Kg8-f7 51.Qc8-d7+ Kf7-g8 ² (0.47) Depth: 5/14 00:00:00 7kN 48...Rg7-g6! ² (0.44) Depth: 5/14 00:00:00 9kN 48...Rg7-g6! 49.Qf5xc5 ² (0.41) Depth: 5/14 00:00:00 9kN 48...Rg7-g6 49.Qf5xc5 Bd1-f3 50.Qc5-f5 Bf3xg2 51.Qf5-d7+ Kh7-g8 52.Kg1xg2 ² (0.34) Depth: 6/15 00:00:00 17kN 48...Rg7-g6 49.Qf5xc5 Bd1-f3 50.Qc5-f5 Bf3xg2 51.Qf5-f7+ Rg6-g7 52.Qf7-f5+ Rg7-g6 53.Qf5-f7+ Rg6-g7 54.Qf7-f5+ = (0.00) Depth: 7/19 00:00:00 51kN 48...Rg7-g6 49.Qf5-f7+ Rg6-g7 50.Qf7-f5+ = (0.00) Depth: 8/22 00:00:00 204kN 48...Rg7-g6 49.Qf5-f7+ Rg6-g7 50.Qf7-f5+ = (0.00) Depth: 9/23 00:00:00 352kN 48...Rg7-g6 49.Qf5-f7+ Rg6-g7 50.Qf7-f5+ = (0.00) Depth: 10/25 00:00:01 1084kN 48...Rg7-g6 49.Qf5-f7+ Rg6-g7 50.Qf7-f5+ = (0.00) Depth: 11/27 00:00:03 2110kN 48...Rg7-g6 49.Qf5-f7+ Rg6-g7 50.Qf7-f5+ = (0.00) Depth: 12/31 00:00:07 4322kN 48...Rg7-g6 49.Qf5-f7+ Rg6-g7 50.Qf7-f5+ = (0.00) Depth: 13/33 00:00:15 9679kN 48...Kh7-h6! = (0.12) Depth: 13/35 00:00:31 19533kN 48...Kh7-h6! 49.Qf5-e6+ Rg7-g6 50.Qe6-e5 Kh6-h7 51.Qe5-c7+ Rg6-g7 52.Qc7xc5 Rg7-f7 53.Qc5-e3 Bd1-f3 54.Qe3-d2 = (-0.19) Depth: 13/35 00:01:04 38122kN 48...Kh7-h6 49.Qf5-e6+ Rg7-g6 50.Qe6-e5 Kh6-h7 51.Qe5-f5 Qh4-g5 52.Qf5xg5 Rg6xg5 53.d3-d4 Bd1-f3 54.d4xc5 = (-0.16) Depth: 14/37 00:01:45 65729kN 48...Kh7-h6 49.Qf5-e6+ Rg7-g6 50.Qe6-e5 Kh6-h7 51.Qe5-c7+ Rg6-g7 52.Qc7-e5 Bd1-h5 53.a2-a3 = (-0.16) Depth: 15/39 00:03:01 113863kN (Blass, Tel-aviv 22.08.2002) Uri
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