Author: Volker Böhm
Date: 16:30:00 08/25/04
Go up one level in this thread
On August 25, 2004 at 13:57:20, GeoffW wrote: >On August 25, 2004 at 12:52:46, Volker Böhm wrote: > >> >>Hi, >> >>the following position of the iq - test (position 166) cannot be solved from >>spike in reasonalbe time (> 2h): >> >>r4r1k/6pp/3p3b/1p1Npb2/3nB2q/2N3P1/PP3P1P/R2Q1RK1 b - - 0 1 >> >>(The move to find is Qxe4) >> >>The reason is a nullmove-problem. After the queen-sac there are many moves that >>leads to a mate-thread. But one queen back spike tends to prune because of >>nullmove result. >> >>I tested the position with fritz 8, he solves it in 8 ply in nearly no time. >>(PRODEO NEEDS 7 Ply, Ruffian 1.01 11 Ply). >> >>Are there non commercial engines that solves this position too in a short amount >>of time? >>Maybe the author of this engine would be so kind to explain the rule that solves >>the nullmove-problem. >> >>Thanks Volker > > >Hello Volker > >I tried it with my program, like yours it couldnt get the correct move even >after a long search. I also disabled my null moving and still it was equally >clueless, so doesn't appear to be a null move issue ? > >I did manage to solve it in ten seconds however by tweaking my Queen value down >from 975 to 900. This then gave the output below. > >What is your Queen value ? 960, thanks thats the clue Volker > > Regards Geoff > > >FEN: r4r1k/6pp/3p3b/1p1Npb2/3nB2q/2N3P1/PP3P1P/R2Q1RK1 b - - 0 1 > > 1 00:00 433 433 +0.02 Qh3 Bxf5 Rxf5 > 2 00:00 886 886 +0.02 Qh3 > 3 00:00 8.848 884.800 -0.08 Qg4 Bxf5 Qxf5 > 4 00:00 16.325 1.632.500 -0.14 Qg4 Bxf5 Qxf5 f4 > 5 00:00 68.848 983.542 -0.14 Qg4 f3 Qh3 Nf4 Bxf4 Bxa8 Bxg3 hxg3 Rxa8 > 6 00:00 165.457 919.205 -0.19 Qg4 Bxf5 Qxf5 f4 Rad8 Rc1 > 7 00:01 819.461 910.512 -0.02 Qh3 > 8 00:02 2.241.365 903.776 -0.11 Qh3 f4 Bxe4 Nxe4 Rfd8 Qd3 Ra4 fxe5 dxe5 > 9 00:10 9.267.108 882.581 +0.31 Qxe4 Nxe4 Bxe4 Nc3 Bf3 Qd3 b4 Rfe1 bxc3 >bxc3 Ra3 > 10 00:18 16.383.527 885.596 +0.21 Qxe4 Nxe4 Bxe4 Nc3 Bf3 Qd3 b4 Rfe1 bxc3 >bxc3 Ra3 Reb1 > 11 00:34 31.049.334 913.215 +0.44 Qxe4 Nxe4 Bxe4 Nc3 Bf3 Qd3 b4 Rfe1 bxc3 >bxc3 Ra3 h4 Rb8 > 12 01:25 74.898.518 881.159 +0.82 Qxe4 Nxe4 Bxe4 Nc3 Bf3 Qd3 b4 Rae1 bxc3 >bxc3 Ra3 Qc4 d5 Qc5 > 13 06:30 339.121.825 869.543 +0.61 Qxe4 Nxe4 Bxe4 Nc3 Bf3 Qd3 b4 Rae1 bxc3 >bxc3 Ra3 Qc4 Nc2 Rb1 Bd2
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.