Plaskett's Chess Puzzle Solved in ~15 minutes

Discussion of anything and everything relating to chess playing software and machines.

Moderators: bob, hgm, Harvey Williamson

Forum rules
This textbox is used to restore diagrams posted with the [d] tag before the upgrade.
Sven
Posts: 3830
Joined: Thu May 15, 2008 7:57 pm
Location: Berlin, Germany
Full name: Sven Schüle
Contact:

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

MikeB wrote:
Fri Oct 26, 2018 3:26 am
; bm Bc2
A position with two black kings? What am I missing?
Sven Schüle (engine author: Jumbo, KnockOut, Surprise)

MikeB
Posts: 3830
Joined: Thu Mar 09, 2006 5:34 am
Location: Pen Argyl, Pennsylvania

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

Sven wrote:
Fri Oct 26, 2018 10:21 am
MikeB wrote:
Fri Oct 26, 2018 3:26 am
; bm Bc2
corrected...
A position with two black kings? What am I missing?
oh geez - thats what I get for trying to handcraft the fen .....the GUI was busy at the time

peter
Posts: 1853
Joined: Sat Feb 16, 2008 6:38 am
Full name: Peter Martan

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

Hi!
Andrew wrote:
Fri Oct 26, 2018 8:27 am
Uri, have you tried it on a recent version of Komodo or any other of the top few engines?
You won't see this result.

I suspect it was just luck or due to engine Parameters
Tried komodo and Houdini both 3 minutes only without solving.
But as for komodo, just switched off LMR- option:

8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1

Analysis by Komodo 12.1.1 64-bit:

Code: Select all

``````1.Nf6+ Kg7
=  (-0.06 --)   Depth: 7   00:00:00  2368kN
1.Nf6+ Kg7
=  (-0.19 --)   Depth: 7   00:00:00  2390kN
1.Nf6+ Kg7
=/+  (-0.45 --)   Depth: 7   00:00:00  2400kN
1.Nf6+ Kg7
=/+  (-0.67 --)   Depth: 7   00:00:00  2443kN
1.Bc2+ Kg7
=/+  (-0.66 --)   Depth: 7   00:00:00  2450kN
1.Bc2+ Kg7
-/+  (-0.96 --)   Depth: 7   00:00:00  2463kN
1.Bc2+ Kg7
-/+  (-1.36 --)   Depth: 7   00:00:00  2470kN
1.Bc2+ Kg7 2.Nxe3 Ba5 3.Nf5+ Kf8 4.Nxh6 Nb4 5.Bb1
-+  (-1.68)   Depth: 7   00:00:00  2519kN
1.Nxe3 Ba5 2.Kd5 Kg6 3.Kc4 Nf7 4.Bc2+ Kf6
-/+  (-1.36)   Depth: 7   00:00:00  2527kN
1.Nxe3 Ba5 2.Kd5 Nf7 3.Bc2+ Kg7 4.Kc4 Ne5+ 5.Kb5 Bd8
-/+  (-1.41)   Depth: 8   00:00:00  2557kN
1.Nxe3 Ba5
-/+  (-1.47 --)   Depth: 9   00:00:00  2647kN
1.Nxe3 c4+ 2.Kd5
-/+  (-1.41 ++)   Depth: 9   00:00:00  2841kN
1.Nxe3 Ba5
-/+  (-1.49 --)   Depth: 9   00:00:00  2846kN
1.Nxe3 Ba5 2.Nd5 Nf7+ 3.Ke7 Kg7 4.Bb3 Ne5 5.Bc2 Nb4
-/+  (-1.44)   Depth: 9   00:00:00  2886kN
1.Nxe3 Ba5 2.Be2
-/+  (-1.37 ++)   Depth: 10   00:00:00  3259kN
1.Nxe3 Ba5 2.Be2 c4 3.Ke7 Nb4 4.Bd1 Kg6 5.Be2 Bc7
-/+  (-1.38)   Depth: 10   00:00:00  3281kN
1.Nxe3 Ba5 2.Be2
-/+  (-1.32 ++)   Depth: 11   00:00:00  3935kN
1.Nxe3 Ba5
-/+  (-1.36 --)   Depth: 11   00:00:00  3964kN
1.Nxe3 Ba5
-/+  (-1.48 --)   Depth: 11   00:00:00  4148kN
1.Nxe3 Ba5
-+  (-1.64 --)   Depth: 11   00:00:00  5390kN
1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Nc6+ 4.Kd6 Nd4 5.Bd3+ Kg7 6.Kxc5 Ngf3 7.Kc4 Kf7 8.Nc2
-/+  (-1.58)   Depth: 11   00:00:00  5695kN
1.Nxe3 Ba5
-+  (-1.64 --)   Depth: 12   00:00:00  6816kN
1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Nc6+ 4.Kd6 Nd4 5.Bd3+ Kg7 6.Kxc5 Nge6+ 7.Kc4 Kf7 8.d8Q Bxd8 9.Kxc3
-+  (-1.72)   Depth: 12   00:00:00  7516kN
1.Nxe3 Ba5
-+  (-1.78 --)   Depth: 13   00:00:01  11837kN
1.Nxe3 Ba5
-+  (-1.87 --)   Depth: 13   00:00:01  15271kN
1.Nxe3 Ba5
-+  (-1.99 --)   Depth: 13   00:00:01  18561kN
1.Kc6 Nb8+ 2.Kc7 Nxd7 3.Kxd7 e2 4.Bxe2 Kg7 5.Ne3 Kf6 6.Kc6 Ne4 7.g4 Ke5 8.Nc2 Kf4 9.Kb5 Nf2 10.Kc4 Nxg4 11.Bd1
-+  (-1.97)   Depth: 13   00:00:01  19184kN
1.Kc6 Nb8+ 2.Kc7 Nxd7 3.Kxd7 e2 4.Bxe2 Kg7 5.Ne3 Kf6 6.Kc6 Ne4 7.g4 Ke5 8.Nc2 Kf4 9.Kb5 Nf2 10.Kc4 Nxg4 11.Bd1
-+  (-1.97)   Depth: 14   00:00:01  20034kN
1.Nxe3 Ba5 2.Kc6
-+  (-1.91 ++)   Depth: 14   00:00:01  21496kN
1.Nxe3 Ba5 2.Kc6
-+  (-1.82 ++)   Depth: 14   00:00:01  22799kN
1.Nxe3 Ba5
-+  (-1.88 --)   Depth: 14   00:00:02  26549kN
1.Nf6+ Kg7 2.Nh5+
-+  (-1.67 ++)   Depth: 14   00:00:02  26742kN
1.Nf6+ Kg7 2.Nh5+
-/+  (-1.46 ++)   Depth: 14   00:00:02  26762kN
1.Nf6+ Kg7 2.Nh5+
-/+  (-1.24 ++)   Depth: 14   00:00:02  26770kN
1.Nf6+ Kg7 2.Nh5+
-/+  (-0.93 ++)   Depth: 14   00:00:02  27008kN
1.Nf6+ Kg7 2.Nh5+
=/+  (-0.51 ++)   Depth: 14   00:00:02  27035kN
1.Nf6+ Kg7 2.Nh5+
=  (0.08 ++)   Depth: 14   00:00:02  27144kN
1.Nf6+ Kg7 2.Nh5+
+/-  (0.89 ++)   Depth: 14   00:00:02  27362kN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Kc6 Ba3 6.Qc8+ Kf3 7.Bd1+ e2 8.Bxe2+ Kxe2 9.Qxa6+ Kd2 10.Qxa3 c2 11.Qa2 Ne4 12.Qd5+ Ke3
+-  (1.66)   Depth: 14   00:00:02  34055kN
1.Nf6+ Kg7 2.Nh5+
+-  (1.72 ++)   Depth: 15   00:00:04  61046kN
1.Nf6+ Kg7 2.Nh5+
+-  (1.81 ++)   Depth: 15   00:00:04  61332kN
1.Nf6+ Kg7 2.Nh5+
+-  (1.93 ++)   Depth: 15   00:00:04  61382kN
1.Nf6+ Kg7 2.Nh5+
+-  (2.09 ++)   Depth: 15   00:00:04  61766kN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qe8 Kf3 6.Bd1+ Kf2 7.Qh5 Ne4+ 8.Ke5 Nxg3 9.Qf3+ Ke1 10.Bb3 e2 11.Qxg3+ Kd2 12.Qf4+ Kd3 13.Qf5+ Kd2 14.Qc2+ Ke3 15.Qc1+ Kd3 16.Bc2+ Kc4 17.Qe3 Kb5
+-  (2.26)   Depth: 15   00:00:04  62934kN
1.Nf6+ Kg7 2.Nh5+
+-  (2.32 ++)   Depth: 16   00:00:06  84759kN
1.Nf6+ Kg7 2.Nh5+
+-  (2.40 ++)   Depth: 16   00:00:06  86023kN
1.Nf6+ Kg7 2.Nh5+
+-  (2.51 ++)   Depth: 16   00:00:06  87687kN
1.Nf6+ Kg7 2.Nh5+
+-  (2.66 ++)   Depth: 16   00:00:06  95421kN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qe8 c4+ 6.Kc6 Bc5 7.Bd1+ Kxg3 8.Qe5+ Kg2 9.Qf5 Be7 10.Qg4+ Kh1 11.Qxc4 Kg1 12.Qxa6 Nh3 13.Qd3 Bg5 14.Bf3 Nf2 15.Qc4 e2 16.Bxe2
+-  (2.85)   Depth: 16   00:00:09  132MN
1.Nf6+ Kg7
+-  (2.79 --)   Depth: 17   00:00:12  186MN
1.Nf6+ Kg7 2.Nh5+
+-  (2.83 ++)   Depth: 17   00:00:15  220MN
1.Nf6+ Kg7 2.Nh5+
+-  (2.94 ++)   Depth: 17   00:00:19  290MN
1.Nf6+ Kg7 2.Nh5+
+-  (3.09 ++)   Depth: 17   00:00:25  343MN
1.Nf6+ Kg7
+-  (2.99 --)   Depth: 17   00:00:25  387MN
1.Nf6+ Kg7 2.Nh5+
+-  (3.13 ++)   Depth: 17   00:00:29  455MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qf6 Kxg3 6.Qe5+ Kf2 7.Qh2+ Ke1 8.Qg1+ Ke2 9.Qg4+ Kf2 10.Bd1 Nb8 11.Qe2+ Kg1 12.Qxe3+ Kh1 13.Kd5 Nd7 14.Qe1+ Kh2 15.Qf2+ Kh1 16.Qh4+ Kg2 17.Qg4+ Kf1 18.Qxd7 Ke1
+-  (3.51)   Depth: 17   00:00:35  551MN
1.Nf6+ Kg7 2.Nh5+
+-  (3.57 ++)   Depth: 18   00:00:52  813MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qf6 Kxg3 6.Qe5+ Kf2 7.Qh2+ Ke1 8.Qg1+ Ke2 9.Qg4+ Ke1 10.Ke5 Kf2 11.Qf4+ Kg2 12.Be4+ Nxe4 13.Kxe4 c2 14.Qf3+ Kh2 15.Qe2+ Kg3 16.Qxe3+ Kg2 17.Qe2+ Kg3
+-  (3.64)   Depth: 18   00:00:53  830MN
1.Nf6+ Kg7 2.Nh5+
+-  (3.70 ++)   Depth: 19   00:01:08  1090MN
1.Nf6+ Kg7 2.Nh5+
+-  (3.78 ++)   Depth: 19   00:01:09  1097MN
1.Nf6+ Kg7 2.Nh5+
+-  (3.89 ++)   Depth: 19   00:01:19  1269MN
1.Nf6+ Kg7 2.Nh5+
+-  (4.04 ++)   Depth: 19   00:01:32  1507MN
1.Nf6+ Kg7 2.Nh5+
+-  (4.25 ++)   Depth: 19   00:02:01  1992MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qf6 Kxg3 6.Qe5+ Kf2 7.Qh2+ Ke1 8.Qg1+ Ke2 9.Qg4+ Ke1 10.Ke5 Kf2 11.Qf4+ Kg2 12.Be4+ Nxe4 13.Kxe4 c2 14.Qf3+ Kh2 15.Qe2+ Kg3 16.Qxe3+ Kg2 17.Qe2+ Kg3 18.Qxc2 c4 19.Kd5 Nc7+ 20.Kxc4 Bc5 21.Qc3+ Kf2
+-  (4.43)   Depth: 19   00:02:05  2074MN
1.Nf6+ Kg7 2.Nh5+
+-  (4.49 ++)   Depth: 20   00:02:49  2793MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qf6 Kxg3 6.Qe5+ Kf2 7.Qh2+ Ke1 8.Qg1+ Ke2 9.Qg4+ Ke1 10.Ke5 c4 11.Bd1 Kf2 12.Kd5 Nc5 13.Qe2+ Kg1 14.Qxe3+ Kf1 15.Kxc4 Na6 16.Qe2+ Kg1 17.Qg4+ Kf2 18.Qh4+ Kg2 19.Qxh6 Nf3 20.Bxf3+ Kxf3 21.Qc6+ Ke2 22.Qxa6
+-  (4.49)   Depth: 20   00:02:49  2795MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qf6 Kxg3 6.Qe5+ Kf2 7.Qh2+ Ke1 8.Qg1+ Ke2 9.Qg4+ Ke1 10.Ke5 c4 11.Bd1 Kf2 12.Kd5 Ba5 13.Qe2+ Kg1 14.Qxe3+ Kg2 15.Qe2+ Kg1 16.Kxc4 Nb4 17.Qe1+ Kg2 18.Qxc3 Nc6 19.Qf6 Nd8 20.Qb2+ Kg3 21.Qa3+ Kf2 22.Qxa5
+-  (4.49)   Depth: 21   00:02:52  2838MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qf6 Kxg3 6.Qe5+ Kf2 7.Qh2+ Ke1 8.Qg1+ Ke2 9.Qg4+ Ke1 10.Ke5 c4 11.Bd1 Kf2 12.Kd5 Ba5 13.Qe2+ Kg1 14.Qxe3+ Kg2 15.Qe2+ Kg1 16.Kxc4 Nb4 17.Qe1+ Kg2 18.Qxc3 Nc6 19.Qf6 Nd8 20.Qb2+ Kg3 21.Qa3+ Kf2 22.Qxa5 Ngf7
+-  (4.49)   Depth: 22   00:03:08  3117MN
1.Nf6+ Kg7 2.Nh5+
+-  (4.55 ++)   Depth: 23   00:04:23  4385MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qf6 Kxg3 6.Qe5+ Kf2 7.Qh2+ Ke1 8.Qg1+ Ke2 9.Qg4+ Ke1 10.Ke5 c4 11.Bd1 Kf2 12.Qe2+ Kg1 13.Qxe3+ Kg2 14.Qe2+ Kg1 15.Kd5 Ba5 16.Qe3+ Kg2 17.Kxc4 Nb4 18.Qxc3 Nc6 19.Qf6 Nd8 20.Qb2+ Kg1 21.Qd4+ Kf1 22.Qf4+ Kg2 23.Qg4+ Kf2
+-  (4.55)   Depth: 23   00:04:26  4436MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qf6 Kxg3 6.Qe5+ Kf2 7.Qh2+ Ke1 8.Qg1+ Ke2 9.Qg4+ Ke1 10.Ke5 c4 11.Bd1 Kf2 12.Qe2+ Kg1 13.Qxe3+ Kg2 14.Qe2+ Kg1 15.Kd5 Ba5 16.Qe3+ Kg2 17.Kxc4 Nb4 18.Qxc3 Nc6 19.Qf6 Nd8 20.Qb2+ Kg1 21.Qd4+ Kf1 22.Qf4+ Kg2 23.Qg4+ Kf2 24.Qf5+ Kg2 25.Qxa5
+-  (4.55)   Depth: 24   00:05:18  5362MN
``````
24 threads of 12x3GHz, 32G hash, no tbs.
Peter.

Uri Blass
Posts: 8730
Joined: Wed Mar 08, 2006 11:37 pm
Location: Tel-Aviv Israel

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

Andrew wrote:
Fri Oct 26, 2018 8:27 am
Uri, have you tried it on a recent version of Komodo or any other of the top few engines?
You won't see this result.

I suspect it was just luck or due to engine parameters which make it better for some positions but worse
for 100s of others.

Engines in your thread which find this quick would be many 100s of elo weaker than the top engines.
McBrain is within a few 10s elo of the top engines, so having this and solving hard problems is
impressive!

Andrew

I still think that if the target is solving test positions without big reduction of playing strength then it is easy to change top engines to solve it fast
and in this case I do not see it logical even to have a reduction in playing strength.

In the relevant case you only need to disable or reduce some reductions in special cases and I do not believe that you will lose hundreds of elo
if you disable these reduction in case that you have a position that you believe to be a losing position(in games you usually do not get a position that you believe to be a losing position when you practically can save it)

Note that after 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ the problem is easy for stockfish and considering the fact that
stockfish has a losing score for white with 1.d8Q(more than 3 pawns disadvantage after a minute) it is strange that it reduce other options so much.

A simple logical rule is that if you have a losing score then try to search more other lines for yourself(including lines that gives you initially a score of -10 instead of working hard to calculate if the main line is -3 or maybe -3.4 because it is not important what is the exact score that you lose but it is important if you can avoid losing).

Note that I do not have latest komodo or houdini so I do not know if they fails to solve the problem in less than 15 minutes with your hardware.

Uri Blass
Posts: 8730
Joined: Wed Mar 08, 2006 11:37 pm
Location: Tel-Aviv Israel

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

tried Rybka2.3.2a that was the best engine and it was optimized for playing strength and not for this position

Rybka solved the problem in slightly more than 1 minute with my slow hardware(3 cores)

FEN: 8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1

Rybka 2.3.2a 64 bit:
5 00:00 1k 89k 0.00 1.Nf6+ Kg7 2.Nh5+ Kg6
6 00:00 3k 81k 0.00 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Nf4+ Kg7
7 00:00 6k 136k -2.50 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Nf4+ Kf5
7 00:00 50k 251k -2.06 1.Nxe3 Ba5 2.Kc6 Nb8+ 3.Kb5
8 00:00 63k 241k -2.07 1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7
9 00:00 78k 256k -2.22 1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Nc6+ 4.Kd6
10 00:00 124k 279k -2.21 1.Nxe3 Ba5 2.Kc6 Nb8+ 3.Kb5 Bd8 4.Bg4 Kg6
11 00:00 214k 304k -2.50 1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Kg7 4.Nf5+ Kh8 5.Bd1
12 00:01 352k 320k -2.51 1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Kg7 4.d8Q Nc6+
13 00:01 572k 338k -2.66 1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Nc6+ 4.Kd6 Nd4 5.Bd3+ Kg7 6.Kxc5 Nge6+ 7.Kc4
14 00:02 786k 341k -2.64 1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Nc6+ 4.Kd6 Nd4 5.Bd1 Ne4+ 6.Kd5 Nxg3 7.Kxc5 Ngf5
15 00:03 1,231k 358k -2.72 1.Nxe3 Ba5 2.Kc6 Nb8+ 3.Kb5 Bc7 4.Kxc5 Nf7 5.Ba4 Ne5 6.Bc2+ Kg8 7.Nf5 Nexd7+
16 00:04 1,694k 366k -2.74 1.Nxe3 Ba5 2.Kc6 Nb8+ 3.Kb5 Bc7 4.Kxc5 Nf7 5.Ba4 Ne5 6.Bc2+ Kg8 7.Nf5 Nexd7+
17 00:09 3,732k 392k -2.75 1.Nxe3 Ba5 2.Kc6 Nb8+ 3.Kb5 Bc7 4.Kxc5 Nf7 5.Ba4 Ne5 6.Bc2+ Kg7 7.Kd4 Nbxd7
17 00:23 8,208k 356k -1.78 1.d8Q Nf7+ 2.Kd7 Nxd8 3.Kxd8 e2 4.Bxe2 c4 5.Ne3 Bc5 6.Nc2 Bf2 7.Kd7 Bxg3
18 00:27 9,497k 349k -1.79 1.d8Q Nf7+ 2.Kd7 Nxd8 3.Kxd8 e2 4.Bxe2 c4 5.Ne3 Bc5 6.Nc2 Bf2 7.Kd7 Bxg3
19 00:36 12,071k 339k -1.82 1.d8Q Nf7+ 2.Kd7 Nxd8 3.Kxd8 e2 4.Bxe2 c4 5.Ne3 Bc5 6.Nc2 Bd6 7.Kd7 Bxg3
20 01:03 18,832k 302k -1.75 1.d8Q Nf7+ 2.Kd7 Nxd8 3.Kxd8 e2 4.Bxe2 c4 5.Ne3 Bc5 6.Nc2 Bd6 7.Kd7 Bxg3
20 01:04 19,142k 303k +3.04 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Bd1+ Kxg3 6.Qe8 c4+ 7.Kc6 Kf4
20 01:04 19,142k 303k +3.04 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Bd1+ Kxg3 6.Qe8 c4+ 7.Kc6 Kf4
21 01:18 23,550k 309k +3.37 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Bd1+ Kxg3 6.Qe8 c4+ 7.Kc6 Kf4

MikeB
Posts: 3830
Joined: Thu Mar 09, 2006 5:34 am
Location: Pen Argyl, Pennsylvania

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

Uri Blass wrote:
Fri Oct 26, 2018 6:43 am
komodo solved it in 2010 in 6.3 seconds on a old hardware of that time
so if people did a special version of stockfish not in order to play but in order to solve chess problems then I find 15 minutes to be a very poor result

viewtopic.php?f=2&t=36156&p=370891&hili ... n1#p370903
McCain was designed was designed for humans to interact with. It includes the cerebellum book functionality, it has a play by ELO option, numerous keyboard shortcuts, and under the PicoChess Raspberry PI, it has connectivity to the DGT board, it has a number of personalities to play against, from the weakest Donald Trump level to the highest McCain level. Since the McBrain/McCain series has started, total downloads are approaching 10,000 and no one has a gun to their head to download. Feel free not to use it, or feel free to use it. It also includes an iron-clad 100% money back guarantee ... it's free ;>)

Dann Corbit
Posts: 10464
Joined: Wed Mar 08, 2006 7:57 pm
Location: Redmond, WA USA
Contact:

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

MikeB wrote:
Fri Oct 26, 2018 6:23 pm
Uri Blass wrote:
Fri Oct 26, 2018 6:43 am
komodo solved it in 2010 in 6.3 seconds on a old hardware of that time
so if people did a special version of stockfish not in order to play but in order to solve chess problems then I find 15 minutes to be a very poor result

viewtopic.php?f=2&t=36156&p=370891&hili ... n1#p370903
McCain was designed was designed for humans to interact with. It includes the cerebellum book functionality, it has a play by ELO option, numerous keyboard shortcuts, and under the PicoChess Raspberry PI, it has connectivity to the DGT board, it has a number of personalities to play against, from the weakest Donald Trump level to the highest McCain level. Since the McBrain/McCain series has started, total downloads are approaching 10,000 and no one has a gun to their head to download. Feel free not to use it, or feel free to use it. It also includes an iron-clad 100% money back guarantee ... it's free ;>)
The original Stockfish suffers mightily on some kinds of positions.
The repair does not make SF the champion at solving these sorts of positions. It makes SF ABLE to solve them in a less than absurd time.
So if you want to let SF validate a large pile of positions it is safer to do so than it used to be.

Additionally, there are variants of SF specifically created for analysis. McCain and CorChess spring to mind. When we use these engines, we do not care if the engine loses a contest of blitz games. We want the right answer when we analyze at long time control. Nothing more and nothing less.

An unfortunate decision of some chess engine writers is to remove everything that does not add Elo, such as underpromotion. Personally, I do not care what happens when one thousand games are played in an hour. I care a lot more about what happens when I analyze a single position for a CPU hour (possibly taking only a minute if I use 60 cores).
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.

Master Om
Posts: 356
Joined: Wed Nov 24, 2010 9:57 am
Location: INDIA

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

MikeB wrote:
Fri Oct 26, 2018 4:00 am
did let it run a bit , but I have to shut it down now:

Code: Select all

``````dep	score	nodes	time	(not shown:  tbhits	knps	seldep)
52	+19.23!	154.7G	1:15:03	Nf6+ Kg7 Nh5+ Kg6 Bc2+ Kxh5 d8=Q Kg4 Qf6 c4+ Kd5 Kxg3 Qf1 Nc7+ Kxc4 Nce6 Kxb4 Nf4 Kxc3 e2 Qe1+ Kg4 Bd3 Kf3 Kd2 Kg4 Bxe2+ Kf5 Bd3+ Kf6 Qh4 Kg7!
51	+19.14!	104.7G	53:12.98	Nf6+ Kg7 Nh5+ Kg6 Bc2+ Kxh5 d8=Q Kg4 Qf6 Kxg3 Qf1 c4+ Kd5 Nc7+ Kxc4 Be7 Qg1+ Kf3 Bd1+ e2 Qf1+ Kg3 Qxe2 Nce6 Qe5+ Kg2 Qxc3 Bc5 Qf6 Be3 Qxh6 Kg3 Qf6 Kg2 Qe5 Bf4 Qe2+ Kg1 Qe1+ Kg2 Bg4 Nd8 Bf5 Nf3 Be4 Nf7 Qe2+ Kg1 Bxf3 Ne5+ Kb5 ``````
Does it solve this in SPV ?
Always Expect the Unexpected

peter
Posts: 1853
Joined: Sat Feb 16, 2008 6:38 am
Full name: Peter Martan

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

Master Om wrote:
Fri Oct 26, 2018 7:44 pm
Does it solve this in SPV ?
Ah, Gusev- Averbakh.
That's again a thing for Sting.
Peter.

Dann Corbit
Posts: 10464
Joined: Wed Mar 08, 2006 7:57 pm
Location: Redmond, WA USA
Contact:

Re: Plaskett's Chess Puzzle Solved in ~15 minutes

Master Om wrote:
Fri Oct 26, 2018 7:44 pm
MikeB wrote:
Fri Oct 26, 2018 4:00 am
did let it run a bit , but I have to shut it down now:

Code: Select all

``````dep	score	nodes	time	(not shown:  tbhits	knps	seldep)
52	+19.23!	154.7G	1:15:03	Nf6+ Kg7 Nh5+ Kg6 Bc2+ Kxh5 d8=Q Kg4 Qf6 c4+ Kd5 Kxg3 Qf1 Nc7+ Kxc4 Nce6 Kxb4 Nf4 Kxc3 e2 Qe1+ Kg4 Bd3 Kf3 Kd2 Kg4 Bxe2+ Kf5 Bd3+ Kf6 Qh4 Kg7!
51	+19.14!	104.7G	53:12.98	Nf6+ Kg7 Nh5+ Kg6 Bc2+ Kxh5 d8=Q Kg4 Qf6 Kxg3 Qf1 c4+ Kd5 Nc7+ Kxc4 Be7 Qg1+ Kf3 Bd1+ e2 Qf1+ Kg3 Qxe2 Nce6 Qe5+ Kg2 Qxc3 Bc5 Qf6 Be3 Qxh6 Kg3 Qf6 Kg2 Qe5 Bf4 Qe2+ Kg1 Qe1+ Kg2 Bg4 Nd8 Bf5 Nf3 Be4 Nf7 Qe2+ Kg1 Bxf3 Ne5+ Kb5 ``````
Does it solve this in SPV ?
McCain may not like the flavor of this one, but Sting finds it to be delicious.

Code: Select all

``````
Searching: 4q1kr/p6p/1prQPppB/4n3/4P3/2P5/PP2B2P/R5K1 w - -
infinite: 0 ponder: 0 time: 0 increment: 0 moves to go: 0
1   +1.01   00:01     280  Bb5
2   +1.05   00:01     580  Bb5 Nf3+ Kg2
3   +2.38   00:01    1060  Bb5 Nf3+ Kf1 Ne5
4   +2.51   00:01    1900  Bb5 a6 Bxc6 Nxc6
5   +2.83   00:01    2833  Bb5 Nf3+ Kg2 Ne5 Bxc6 Nxc6
6   +3.76   00:01    5067  Bb5 Nf3+ Kg2 Ne5 Bxc6 Nxc6 Qd7
7   +0.48   00:01   13184  Qd5 Rxe6 Rf1 Nf7 Bc4 Nxh6 Qxe6+ Qxe6
8   -0.65   00:01   37809  Qd5 Rxe6 Rf1 Kf7 Bb5 Qc8 Bg5 Qc5+ Kg2 Qxd5 exd5
9   -0.65   00:01   44890  Qd5 Rxe6 Rf1 Kf7 Bb5
10   -0.48   00:01  143272  Qd5 Rxe6 a4 Qc8 a5 Qc5+ Kh1 Qxd5 exd5 Re8 axb6
11   -0.61   00:01  282449  Qd5 Rxe6 Rf1 Kf7 Qb3 Qc6 Rf4 Qc5+ Kh1 Qe7 Qd5 Rd8
12   -0.69   00:01   1043K  Qa3 Rxe6 Rd1 Qb8 Qb3 Kf7 Rf1 Qd6 Kg2 Qe7 Bb5
13   -0.53   00:01   1122K  Qa3 Rxe6 Rd1 Qb8 Qb3 Kf7 Bg4 Qc8 Bxe6+ Qxe6 Qa4 a6 Kh1 a5 Be3 Kg7 a3 Rc8 Qd4
14   -0.44   00:01   1361K  Qa3 Rxe6 Rd1 Qb8 Qb3 Kf7 Bg4 Qc8 Bxe6+ Qxe6 Bf4 Qxb3 axb3 Ke6 Rd5 Nf7 Kg2 g5 Bg3 Rc8
15   -0.57   00:01   2904K  Qa3 Rxe6 Rd1 Kf7 Qxa7+ Qe7 Qa4 Rd8 Rxd8 Qxd8 h3 Qc8 Kg2 Rd6 Be3 Qe6 Qa6 b5 Qxb5 Qxa2
16   -0.57   00:01   3150K  Qa3 Rxe6 Rd1 Kf7 Qxa7+ Qe7 Qa4 Rd8 Rxd8
17   +0.00   00:02   5044K  Qa3 Rxe6 Qxa7 Nf7 Bc4 Rxe4 Qc7 b5 Bb3 g5 Rd1 Re7 Rd8 Re1+ Kg2 Re2+ Kg1 Re1+
18   +0.00   00:02   6124K  Qa3 Rxe6 Qxa7 Nf7 Bc4 Rxe4 Qc7 b5 Bb3 g5 Rd1 Re1+ Rxe1 Qxe1+ Kg2 Qe2+ Kg1 Qe1+
19   +0.00   00:02   8099K  Qa3 Rxe6 Qxa7 Qe7 Qa8+ Qe8 Qa7
20   +0.00   00:02   9499K  Qa3 Rxe6 Qxa7 Qe7 Qa8+ Qe8 Qa7
21   +0.00   00:02   9976K  Qa3 Rxe6 Qxa7 Qe7
22   +0.00   00:03  12074K  Qa3 Rxe6 Qxa7 Qe7 Qa8+ Qe8 Qa7
23   +0.00   00:03  15780K  Qa3 Rxe6 Qxa7 Qe7 Qa8+ Qe8 Qa7
24   +0.00   00:06  36601K  Qa3
25   +0.00   00:06  43861K  Qa3 Rxe6 Qxa7 Qe7 Qa8+ Qe8 Qa7
26   +0.00   00:08  57678K  Qa3 Rxe6 Qxa7 Qe7 Qa8+ Qe8 Qa7
27   +0.00   00:10  70796K  Qa3 Rxe6 Qxa7 Qe7 Qa8+ Qe8 Qa7
28   +0.00   00:12  90569K  Qa3 Rxe6 Qxa7 Qe7 Qa8+ Qe8 Qa7
29   +0.00   00:16 127946K  Qa3 Rxe6 Qxa7
30   +1.90   00:22 195440K  Qxe5 fxe5 Rf1 Rc7 Bb5 Qe7 Ba4 b5 Bb3 Rc4 Kg2 Qe8 Bxc4 bxc4 b3 cxb3 axb3 a5 Kg3 Qe7 Rf2 Qe8 c4 Qe7 Kg2 Qa3 Rf3 Qe7 Rf1 Qa3
31   +1.90   00:26 234663K  Qxe5 fxe5 Rf1 Rc7 Bb5 Qe7 Ba4 b5 Bb3 Rc4 Kg2 Qe8 Bxc4 bxc4 b3 cxb3 axb3 a5 Kg3 Qe7 Rf2 Qe8 Rf3 Qe7 Rf1 Qc5 Kg2 Qe7 Rf3 Qe8 c4 Qe7
32   +2.55   00:44 424790K  Qxe5 fxe5 Rf1 Rc7 Bb5 Qe7 Ba4 b5 Bb3 Rc4 a4 a6 Kg2 Qe8 Rf3 Qe7 axb5 axb5 Ba2 Qg7 Bxc4 bxc4 Bxg7 Kxg7 Rf7+ Kh6 e7 Re8 Kf3 g5 Rf6+ Kg7 Re6 Kf7 Rxe5 Rxe7 Rxe7+ Kxe7 Ke3 Kd6 Kd4 g4 Kxc4 Ke5 Kd3
33   +2.59   01:05 646708K  Qxe5 fxe5 Rf1 a6 Bd1 b5 Bb3 Rc4 Rf3 g5 Kg2 Qe7 Rf5 Qd8 a4 Qe7 Ba2 Qg7 Bxg7 Kxg7 Bxc4 bxc4 e7 Re8 Rxe5 Kf7 Kf3 Rxe7 Rxe7+ Kxe7 Ke3 Kd6 Kd4 g4 a5 Ke6 Kxc4
34   +2.87   01:27 861292K  Qxe5 fxe5 Rf1 Qe7 Bd1 Rc4 Bb3 b5 a4 a6
35   +2.87   01:40   1001M  Qxe5 fxe5 Rf1 Qe7 Bd1 Rc4 Bb3 b5 a4 a6 Kg2 Qe8 Rf3 Qe7 Ba2 Qg7 Bxg7 Kxg7 Bxc4 bxc4 Rf7+ Kh6 Ra7 Rb8 Kg3 g5 Rxa6 Kg6 a5 Kf6 Rb6 Ra8 a6 h5 Kf3 Ke7 Rb7+ Kxe6 Rh7 Kf6 a7 Kg6 Rc7 Kf6 Rc6+ Ke7 Rh6
36   +3.11   02:20   1414M  Qxe5 fxe5 Rf1 Qe7 Bd1 Rc4 Bb3 b5 a4 a6 Kg2 Qe8 Ba2 Qa8 Kg3 Qe8 Rf3 g5 Kg2 Qe7 b4 Qg7 Bxg7 Kxg7 Bxc4 bxc4 Rf5 Re8 Rxg5+ Kf6 Rh5 Rxe6 Rh6+ Kf7 Rxh7+ Kg6 Rc7 Kg5 Kg3 Rg6 Rxc4 Rg8
37   +3.47   03:24   2100M  Qxe5 fxe5 Rf1 Qe7 Bd1 Rc4 Bb3 b5 a4 a6 Kg2 Qg7 Bxg7 Kxg7 Rf7+ Kh6 Bxc4 bxc4 e7 Re8 Kg3 g5 Rf6+ Kg7 Rxa6 Rxe7 Kg4 Rb7 Kxg5 Rxb2 Ra7+ Kg8 Kf6 Rf2+ Kxe5 Rxh2 a5 Ra2 Kd5 h5 e5 Kf8 a6
38   +4.00   09:23   5990M  Qxe5 fxe5 Rf1 Qe7 Bd1 Rc4 Bb3 b5 a4 a6 Kg2 Qg7 Bxc4 bxc4 Bxg7 Kxg7 Rf7+ Kh6 e7 Re8 Kg3 Kh5 Rxh7+ Kg5 Rf7 Kh5 h4 g5 hxg5 Kxg5 Rf5+ Kg6 Rxe5 Kf7 Rc5 Kxe7 Rxc4 Kd6 Kf4 Rf8+ Ke3 Rh8 Rd4+ Ke6 Rd5 Rh2 b3 Rh3+
``````
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.