Discussion of anything and everything relating to chess playing software and machines.
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Spliffjiffer
Posts: 416Joined: Thu Aug 02, 2012 7:48 pmLocation: Germany
Post by Spliffjiffer Fri Oct 18, 2013 5:08 pm
Which engine can find the best move here, and how long does it take ?
[D] 3R4/1kr2pp1/2p1p3/1pP1PnBP/pP2K3/8/P4P2/8 w - - 0 1
1. a3!!
This is from an old game of Kramnik vs Bacrot (i believe)...Kramnik played 1.Kf4 and won after 1...Rc8 2.Rd7 Rc7 3.Rd3 Kc8 4.Rd8 Kb7 5.Bf6! g6 quite quickly
Instead of 1.Kf4!, the move 1.a3!! is already a forced win but after some research i couldnt find any program that found that simple (zugzwang-) move on my small hardware
...maybe the program and the hardware are out there
a line eg is :
1.a3!! Rc8 2.Rd7 Rc7 3.Rd3 Kb8 4.Kf4 Kc8 5.Rd8...and analog to the Kramnik game
Wahrheiten sind Illusionen von denen wir aber vergessen haben dass sie welche sind.
jdart
Posts: 4367Joined: Fri Mar 10, 2006 5:23 amLocation: http://www.arasanchess.org
Post by jdart Fri Oct 18, 2013 5:22 pm
The game was Kramnik-Bareev, Wijk aan Zee 2003. Kramnik played Rd1 and eventually won. I am not sure a3 is actually best here.
Spliffjiffer
Posts: 416Joined: Thu Aug 02, 2012 7:48 pmLocation: Germany
Post by Spliffjiffer Fri Oct 18, 2013 5:42 pm
you are right...thanks for clarification
after 1.a3 the sequence is forced....if you dont play 1.a3 then black can do it and its not that clear afai can see
regards
Wahrheiten sind Illusionen von denen wir aber vergessen haben dass sie welche sind.
zullil
Posts: 6442Joined: Tue Jan 09, 2007 12:31 amLocation: PA USAFull name: Louis Zulli
Post by zullil Fri Oct 18, 2013 6:28 pm
jdart wrote: The game was Kramnik-Bareev, Wijk aan Zee 2003. Kramnik played Rd1 and eventually won. I am not sure a3 is actually best here.
lech
Posts: 1136Joined: Sun Feb 14, 2010 10:02 pm
Post by lech Mon Oct 21, 2013 11:24 am
[d]3R4/1kr2pp1/2p1p3/1pP1PnBP/pP2K3/8/P4P2/8 w - - bm a3;
Sting-sf-4 (work in progreass) gets it in 40 minutes on dual core.
It means there are computers able to find it in play.
Code: Select all
info depth 42 seldepth 53 multipv 1 score cp 117 nodes 1978043266 nps 908140 tim
e 2178125 pv e4f4 a4a3 f4g4 c7c8 d8d7 c8c7 d7d3 b7c8 d3d8 c8b7 g4f4 c7c8 d8d7 c8
c7 d7d3 b7c8 d3a3 c8b7 f4e4 c7d7 a3d3 d7d5 d3d5 c6d5 e4d3 b7c6
info depth 43
info currmove e4f4 currmovenumber 1
info nodes 2112997025 nps 907827 time 2327531
info currmove a2a3 currmovenumber 2
info depth 43 seldepth 0 multipv 1 score cp 125 lowerbound nodes 2209923787 nps
906135 time 2438844 pv a2a3
info nodes 2209923787 nps 906135 time 2438844
info currmove a2a3 currmovenumber 1
info depth 43 seldepth 0 multipv 1 score cp 133 lowerbound nodes 2255082100 nps
906019 time 2489000 pv a2a3
info nodes 2255082100 nps 906019 time 2489000
info currmove a2a3 currmovenumber 1
info depth 43 seldepth 0 multipv 1 score cp 145 lowerbound nodes 2321803748 nps
905313 time 2564641 pv a2a3
info nodes 2321803748 nps 905313 time 2564641
info currmove a2a3 currmovenumber 1
info depth 43 seldepth 0 multipv 1 score cp 163 lowerbound nodes 2457213286 nps
905978 time 2712219 pv a2a3
info nodes 2457213286 nps 905978 time 2712219
info currmove a2a3 currmovenumber 1
info depth 43 seldepth 0 multipv 1 score cp 190 lowerbound nodes 2672460633 nps
906394 time 2948453 pv a2a3
info nodes 2672460633 nps 906394 time 2948453
info currmove a2a3 currmovenumber 1
info nodes 2755004763 nps 906545 time 3039016
info currmove e4f4 currmovenumber 2
info currmove g5f4 currmovenumber 3
info currmove g5f6 currmovenumber 4
info nodes 2794013390 nps 906632 time 3081750
info currmove d8d7 currmovenumber 5
info currmove e4f3 currmovenumber 6
info nodes 2794574190 nps 906634 time 3082359
info currmove h5h6 currmovenumber 7
info currmove d8e8 currmovenumber 8
info currmove d8d6 currmovenumber 9
info nodes 2796100739 nps 906601 time 3084156
info currmove d8b8 currmovenumber 10
info currmove d8a8 currmovenumber 11
info currmove d8h8 currmovenumber 12
info currmove e4d3 currmovenumber 13
info currmove g5c1 currmovenumber 14
info currmove f2f4 currmovenumber 15
info currmove g5e3 currmovenumber 16
info currmove d8g8 currmovenumber 17
info currmove d8f8 currmovenumber 18
info currmove d8d1 currmovenumber 19
info nodes 2797092339 nps 906592 time 3085281
info currmove d8c8 currmovenumber 20
info currmove g5h4 currmovenumber 21
info currmove g5e7 currmovenumber 22
info currmove g5d2 currmovenumber 23
info currmove d8d2 currmovenumber 24
info nodes 2797815301 nps 906587 time 3086094
info currmove d8d4 currmovenumber 25
info currmove d8d3 currmovenumber 26
info currmove f2f3 currmovenumber 27
info currmove g5h6 currmovenumber 28
info currmove d8d5 currmovenumber 29
info depth 43 seldepth 57 multipv 1 score cp 165 nodes 2798229683 nps 906584 tim
e 3086562 pv a2a3 c7c8 d8d7 c8c7 d7d3 b7c8 d3d8 c8b7 e4f3 c7c8 d8d7 c8c7 d7d2 b7
c8 d2d8 c8b7 f3f4 c7c8 d8d7 c8c7 d7d1 b7c8 d1d8 c8b7 f4f3Maybe, I can't be friendly, but let me be useful.
Spliffjiffer
Posts: 416Joined: Thu Aug 02, 2012 7:48 pmLocation: Germany
Post by Spliffjiffer Mon Oct 21, 2013 3:50 pm
Thank you Marek for your investigation...so the problem seems to be quite hard for our all engines
....nice, to have seen one confirmation that 1.a3 is best here...for a human quite easy to understand imo after you entered the position "by brain"
regards
Wahrheiten sind Illusionen von denen wir aber vergessen haben dass sie welche sind.
Eelco de Groot
Posts: 4567Joined: Sun Mar 12, 2006 2:40 amFull name:
Post by Eelco de Groot Mon Oct 21, 2013 3:59 pm
Good to see that you are working on Sting 4 Marek!45 7:49 +1.19 40.a3 Rc8 41.Rd7+ Rc7 42.Rd3 Kc8 45 7:49 +1.19 40.Kf3 Rc8 41.Rd7+ Rc7 42.Rd1 Kc8 54 574:38 +2.77++ 40.Kf4 Rc8 41.Rd7+ (127.230.759.804) 3690 53 574:38 +1.19 40.a3 Rc8 41.Rd7+ Rc7 42.Rd3 Kc8 55 751:38 +2.16 40.Kf4 a3 41.Bf6 gxf6 42.exf6 Rc8 54 751:38 +1.19 40.a3 Rc8 41.Rd7+ Rc7 42.Rd3 Kc8
Debugging is twice as hard as writing the code in the first
lech
Posts: 1136Joined: Sun Feb 14, 2010 10:02 pm
Post by lech Mon Oct 21, 2013 9:13 pm
Eelco de Groot wrote: [..] I'm not sure that the solution from Peer is the best though.[...]
The sacrifice move Bf6! should lead to win in both the possible continuations with white or black pawn on a3 (1.Kf4! a3 or 1.a3!).
Maybe, I can't be friendly, but let me be useful.
lech
Posts: 1136Joined: Sun Feb 14, 2010 10:02 pm
Post by lech Tue Oct 22, 2013 2:13 pm
Eelco de Groot wrote: Good to see that you are working on Sting 4 Marek!45 7:49 +1.19 40.a3 Rc8 41.Rd7+ Rc7 42.Rd3 Kc8 45 7:49 +1.19 40.Kf3 Rc8 41.Rd7+ Rc7 42.Rd1 Kc8 54 574:38 +2.77++ 40.Kf4 Rc8 41.Rd7+ (127.230.759.804) 3690 53 574:38 +1.19 40.a3 Rc8 41.Rd7+ Rc7 42.Rd3 Kc8 55 751:38 +2.16 40.Kf4 a3 41.Bf6 gxf6 42.exf6 Rc8 54 751:38 +1.19 40.a3 Rc8 41.Rd7+ Rc7 42.Rd3 Kc8
Eelco, in the third Multi PV White (Stockfish) can play better 48.Bf6! (instead of Kf3) and it leads to win as two earlier PVs.
Maybe, I can't be friendly, but let me be useful.
Eelco de Groot
Posts: 4567Joined: Sun Mar 12, 2006 2:40 amFull name:
Post by Eelco de Groot Tue Oct 22, 2013 5:18 pm
lech wrote:
Eelco, in the third Multi PV White (Stockfish) can play better 48.Bf6! (instead of Kf3) and it leads to win as two earlier PVs.
That would be a nice possibility Marek, three variations, but all including that same sacrifice. I had not seen that move in the PVs yet. It seems pretty hard to find at least for my EvalMarginV branch; the earliest it shows up is at a plydepth of 50. That is after one hour in MultiPV in this case:
50 60:45 +1.19 40.a3 Rc8 41.Rd7+ Rc7 42.Rd3 Kc8 43.Rd8+ Kb7 44.Kf4 Rc8 45.Rd7+ Rc7 46.Rd3 Kc8 47.Rd8+ Kb7 48.Kf3 Rc8 49.Rd7+ Rc7 50.Rd1 Kb8 51.Kf4 Kc8 52.Rd8+ (13.039.909.106) 3577
50 60:45 +1.45++ 40.Kf4 a3
41.Bf6 gxf6 42.exf6 Rc8 43.Rd7+ Rc7 44.Rxc7+ Kxc7 45.Kg5 Nd4 (13.039.909.106) 3577
49 60:45 +1.37 40.Kf3 Rc8 41.Rd7+ Rc7 42.Rd1 Kc8 43.Rd8+ Kb7 44.Kf4 a3 45.Kf3 Ka7 46.Rd3 Kb8 47.Rd2 Ka8 48.Rd1 Kb8 49.Rd3 Kc8 50.Rd8+ Kb7 51.Ke2 Ka7 52.Rd3 Kb8 53.Kd1 (13.039.909.106) 3577
It's a long distance testmove!
Regards, Eelco
Debugging is twice as hard as writing the code in the first
