Discussion of anything and everything relating to chess playing software and machines.
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F. Bluemers
Posts: 880Joined: Thu Mar 09, 2006 11:21 pmLocation: Nederland
Post by F. Bluemers Sun Feb 21, 2010 7:07 pm
[d] 8/1p3kp1/p3p2p/1bR1P1q1/1P2B3/P4P2/5P1K/2R5 b - -
Fresh from CCT12!
instead of taking a draw with perpetual checks,Dirty played b6 ,loosing the ability to force a draw but also getting into a terrible bind.
I thought this was just typical for dirty but no:
Code: Select all
Rybka 2.2n2 1 core
14.01 0:01 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (327.072) 200
15.01 0:02 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (538.385) 207
16.01 0:04 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (908.075) 212
17.01 0:07 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (1.537.290) 215
18.01 0:11 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (2.504.578) 216
19.01 0:19 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (4.158.050) 214
20.01 0:34 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (7.143.381) 215
21.01 1:00 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (12.623.838) 213
22.01 1:47 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T1c7+ Ld7 36.Lc6 Dxe5+ (22.253.084) 212Code: Select all
Spike 1.2 Turin
12.01 0:01 +0.58 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T8c7+ Ld7 36.Lb7 Dxe5+ 37.Kg2 Kd8 38.Lxa6 Dxc7 39.Txc7 Kxc7 40.Lc4 (1.539.694) 1139
13.01 0:01 +0.61 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T8c7+ Ld7 36.Lb7 Dxe5+ 37.Kg1 Kd8 38.T7c4 a5 39.f4 De2 40.bxa5 bxa5 41.Le4 (2.218.753) 1159
13.03 0:02 +0.61 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T8c7+ Ld7 36.Lb7 Dxe5+ 37.Kg1 Kd8 38.T7c4 a5 39.f4 De2 40.bxa5 bxa5 41.Le4 (2.637.012) 1161
14.03 0:02 +0.31-- 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T8c7+ Ld7 36.Lb7 Dxe5+ 37.Kg1 Kd8 38.T7c4 a5 39.f4 De2 40.bxa5 bxa5 41.Le4 Lb5 (3.258.469) 1160
14.18 0:05 +0.31-- 32...b6 33.Tc7+ Kf8 34.Tc8+ Ke7 35.T8c7+ Ld7 36.Lb7 Dxe5+ 37.Kg1 Kd8 38.T7c4 a5 39.f4 De2 40.bxa5 bxa5 41.Le4 (6.073.752) 1160
14.01 0:06 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg1 Dg5+ 37.Kh2 Dh5+ 38.Kg3 Dg5+ 39.Kh2 (7.589.207) 1166
14.05 0:07 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg1 Dg5+ 37.Kh2 Dh5+ 38.Kg3 Dg5+ 39.Kh2 (8.926.892) 1163
15.01 0:08 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg1 Dg5+ 37.Kh2 Dh5+ 38.Kg3 Dg5+ 39.Kh2 (10.406.704) 1174
15.09 0:13 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg1 Dg5+ 37.Kh2 Dh5+ 38.Kg3 Dg5+ 39.Kh2 (15.657.833) 1161
16.01 0:15 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg1 Dg5+ 37.Kh2 Dh5+ 38.Kg3 Dg5+ 39.Kh2 (18.440.291) 1172
16.07 0:19 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg1 Dg5+ 37.Kh2 Dh5+ 38.Kg3 Dg5+ 39.Kh2 (22.341.117) 1169
17.01 0:23 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg1 Dg5+ 37.Kh2 Dh5+ 38.Kg3 Dg5+ 39.Kh2 (28.133.761) 1183
17.02 0:25 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg1 Dg5+ 37.Kh2 Dh5+ 38.Kg3 Dg5+ 39.Kh2 (30.544.636) 1177Code: Select all
Fruit 2.2.1
13/30 0:01 +0.11 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c6 Dxe5+ 36.Kg2 Dg5+ 37.Kh1 Ke7 38.Txb6 Lb5 39.Tc7+ Kf6 40.Tb8 Dh4+ 41.Kg2 g6 42.Tf8+ Kg5 (2.863.623) 1516
14/34 0:03 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c7 Dxe5+ 36.Kg2 Dg5+ 37.Kh3 Dh5+ 38.Kg3 Dg5+ 39.Kh3 (5.200.650) 1495
15/40 0:06 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c7 Dxe5+ 36.Kg2 Dg5+ 37.Kh3 Dh5+ 38.Kg3 Dg5+ 39.Kh3 (9.282.817) 1524
16/45 0:10 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c7 Dxe5+ 36.Kg2 Dg5+ 37.Kh3 Dh5+ 38.Kg3 Dg5+ 39.Kh3 (16.322.468) 1535
17/45 0:18 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c7 Dxe5+ 36.Kg2 Dg5+ 37.Kh3 Dh5+ 38.Kg3 Dg5+ 39.Kh3 (27.640.706) 1529
18/45 0:30 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c7 Dxe5+ 36.Kg2 Dg5+ 37.Kh3 Dh5+ 38.Kg3 Dg5+ 39.Kh3 (47.025.497) 1534
19/53 1:15 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c7 Dxe5+ 36.Kg2 a5 37.bxa5 Dg5+ 38.Kf1 Db5+ 39.Kg2 Dg5+ (113.514.035) 1503
20/53 2:06 0.00 32...b6 33.Tc7+ Kf8 34.Tc8+ Le8 35.T1c7 Dxe5+ 36.Kg2 a5 37.bxa5 Dg5+ 38.Kf1 Db5+ 39.Kg2 Dg5+ (189.322.845) 1500
zullil
Posts: 6442Joined: Tue Jan 09, 2007 12:31 amLocation: PA USAFull name: Louis Zulli
Post by zullil Sun Feb 21, 2010 7:25 pm
F. Bluemers wrote: [d] 8/1p3kp1/p3p2p/1bR1P1q1/1P2B3/P4P2/5P1K/2R5 b - -
Stockfish-1.6.3 (8 threads):
Code: Select all
Searching: 8/1p3kp1/p3p2p/1bR1P1q1/1P2B3/P4P2/5P1K/2R5 b - -
infinite: 0 ponder: 0 time: 0 increment: 0 moves to go: 0
2 -0.48 00:01 859 Qe7 Rc7
2 -0.08 00:01 1029 Qh4+ Kg2 Qg5+ Kh3
3 +0.00 00:01 1803 Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
4 +0.00 00:01 2496 Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
5 +0.00 00:01 3410 Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
6 +0.00 00:01 5383 Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
7 +0.00 00:01 7435 Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
8 +0.00 00:01 10351 Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
9 +0.00 00:01 16927 Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
9 > +0.20 00:01 32423 b6 Rc7+ Kf8 Kh3 Qxe5 Kg4 Qg5+ Kh3 h5
10 +0.00 00:01 111401 b6 Rc7+ Kf8 Rc8+ Ke7 R1c7+ Bd7 Bc6 Qxe5+ Kg2 Qg5+
Kf1 Qc1+ Kg2 Qg5+
11 +0.00 00:01 161418 b6 Rc7+ Kf8 Rc8+ Ke7 R1c7+ Bd7 Bc6 Qxe5+ Kg2 Qg5+
Kf1 Qc1+ Kg2 Qg5+
12 +0.00 00:01 268740 b6 Rc7+ Kf8 Rc8+ Ke7 R1c7+ Bd7 Bc6 Qxe5+ Kg2 Qg5+
Kf1 Qc1+ Kg2 Qg5+
13 +0.00 00:01 379321 b6 Rc7+ Kf8 Rc8+ Ke7 R1c7+ Bd7 Bc6 Qxe5+ Kg2 Qg5+
Kf1 Qc1+ Kg2 Qg5+
14 +0.00 00:01 670246 b6 Rc7+ Kf8 Rc8+ Ke7 R1c7+ Bd7 Bc6 Qxe5+ Kg2 Qg5+
Kf1 Qc1+ Kg2 Qg5+
15 +0.00 00:01 1100k b6 Rc7+ Kf8 Rc8+ Ke7 R1c7+ Bd7 Bc6 Qxe5+ Kg2 Qg5+
Kf1 Qc1+ Kg2 Qg5+
16 +0.00 00:01 2475k b6 Rc7+ Kf8 Rc8+ Be8 R1c7 Qxe5+ Kg2 Qg5+ Kh2 Qh5+
Kg2 Qg5+
17 < -0.20 00:01 3867k b6 Rc7+ Kf8 Rc8+ Be8 R1c7 Qxe5+ Kg2 Qg5+ Kf1 Qe5
Bc6 Qa1+ Kg2
17 +0.00 00:02 9498k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
18 +0.00 00:02 10699k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
19 +0.00 00:03 13446k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
20 +0.00 00:03 17520k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
21 +0.00 00:04 24642k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
22 +0.00 00:06 36365k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
23 +0.00 00:08 59532k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
24 +0.00 00:13 102428k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
25 +0.00 00:20 165242k Qh4+ Kg2 Qg5+ Kh3 Qh5+ Kg2 Qg5+
Nodes: 252508788
Nodes/second: 8349882
Best move: Qh4+
Ponder move: Kg2
Edmund
Posts: 670Joined: Mon Dec 03, 2007 3:01 pmLocation: Barcelona, Spain
Post by Edmund Sun Feb 21, 2010 10:39 pm
F. Bluemers wrote: 8/1p3kp1/p3p2p/1bR1P1q1/1P2B3/P4P2/5P1K/2R5 b - -
We need some more intelligent root-level-search:
1) if there is a way to force draw at the root:
2) increase the search time considerably
3) if after that time no other move with score > contempt-value has been found: force the draw
other option:
return higher drawscores for lower ply counts (but this is more difficult concerning search instability)
regards,
Edmund
UncombedCoconut
Posts: 319Joined: Fri Dec 18, 2009 11:40 amLocation: Naperville, IL
Post by UncombedCoconut Mon Feb 22, 2010 12:01 am
Depending on luck, Stockfish may like 1...b6 but still see the perpetual. Relevant blip in its thinking on my laptop:
Code: Select all
8 +0.00 32.... Qh4+ 33.Kg2 Qg5+ 34.Kh3 Qh5+ 35.Kg2 Qg5+ (0.19)
9 +0.00 32.... Qh4+ 33.Kg2 Qg5+ 34.Kh3 Qh5+ 35.Kg2 Qg5+ (0.20)
9 -0.20 32.... b6 33.Rc7+ Kf8 34.Kh3 Qxe5 35.Kg4 Qg5+ 36.Kh3 Qf4 (0.20)
10 -0.44 32.... b6 33.Rc7+ Kf8 34.Kh3 Qxe5 35.Kg4 Bd7 36.Bb7 Qg5+ 37.Kh3 e5+ 38.Kh2 Qh5+ 39.Kg2 Qg6+ 40.Kh2 (0.28)
11 +0.00 32.... b6 33.Rc7+ Kf8 34.Rc8+ Ke7 35.R1c7+ Bd7 36.Bc6 Qxe5+ 37.Kg2 Qg5+ 38.Kf1 Qc1+ 39.Kg2 Qg5+ (0.38)
OK, these lines delay the inevitable unnecessarily, but in OTB play a draw is a draw.
I think this is at worst a tiny problem.
FWIW play continued 32.... b6 33.Rc7+ Kf8 34.Rc8+ Be8? , throwing away the draw two moves later. If you throw the position before Be8 at engines they'll hopefully all agree on Ke7.
[d] 2R2k2/6p1/pp2p2p/1b2P1q1/1P2B3/P4P2/5P1K/2R5 b - -
I think this is at worst a tiny problem.