Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: and I also got confused!

Author: Roy Brunjes

Date: 14:19:18 02/23/03

Go up one level in this thread


On February 23, 2003 at 16:27:08, Mike Byrne wrote:

>On February 23, 2003 at 16:23:16, Mike Byrne wrote:
>
>>Ruffian , among others, like Shredder 7,  gets confused by this position,  It
>>thinks it's mate in 18 for black and plays Kxd7 -- which, unfortunately leads to
>>a Mate in 18 for BLACK!.  The problem here is that the EGTB does not recognizing
>
>a mate in 18 for WHITE after Kxd7??
>
>
>
>>castling rights and the program is not examining them either.
>>
>>Proper play is Kd8 and black mates in 18
>>
>>[d] 2k5/3P4/8/8/8/8/1r5p/R3K3 b Q - 0 1
>>
>>Ruffian 1.0.1 analysis
>>
>>New game
>>2k5/3P4/8/8/8/8/1r5p/R3K3 b Q - 0 1
>>
>>Analysis by Ruffian 1.0.1:
>>
>>1. -+ (-#17): 1...Kxd7 2.0-0-0+ Ke6 3.Kxb2 Kf5
>>2. -+ (-#18): 1...Kd8 2.Ra8+ Kxd7
>>
>>(Byrne, Secane, PA USA 23.02.2003)
>>
>>Proper Analysis:
>>
>>
>>If black plays Kxd7, then it is mate for white in 18 with 0-0-0 as shown by
>>Fritz 8.
>>
>>
>>[d]8/3k4/8/8/8/8/1r5p/R3K3 w Q - 0 1
>>
>>Analysis by Fritz 8:
>>
>>1. +- (#18): 2.0-0-0+ Ke6 3.Kxb2 Ke5 4.Kc3
>>2. -+ (-#16): 2.Ra7+ Kc6 3.Rh7 h1Q+ 4.Rxh1 Rb1+
>>
>>(Byrne, Secane, PA USA 23.02.2003)

Junior 7 also has the same problem:

New game
2k5/3P4/8/8/8/8/1r5p/R3K3 b Q - 0 1

Analysis by Junior 7:

1...Kxd7 2.0-0-0+
  ±  (1.28)   Depth: 3   00:00:00
1...Kb7 2.d8Q h1Q#
  =  (0.06)   Depth: 3   00:00:00
1...Kc7 2.0-0-0
  ³  (-0.61)   Depth: 3   00:00:00
1...Kd8 2.0-0-0
  µ  (-0.80)   Depth: 3   00:00:00
1...Kd8!
  µ  (-1.10)   Depth: 6   00:00:00
1...Kd8 2.0-0-0 Rg2 3.Rd2
  -+  (-10.52)   Depth: 6   00:00:00
1...Kxd7!
  -+  (-#17)   Depth: 6   00:00:00, tb=1
1...Kxd7
  -+  (-#17)   Depth: 6   00:00:00, tb=2

(Brunjes, MyTown 23.02.2003)

Fritz 8 does not have the problem however:

New game
2k5/3P4/8/8/8/8/1r5p/R3K3 b Q - 0 1

Analysis by Fritz 8:

1...Kd8 2.0-0-0 Rg2 3.Kb1 Rg1 4.Rc1 h1Q
  -+  (-9.84)   Depth: 7/17   00:00:00  24kN, tb=10
1...Kd8 2.0-0-0 Rg2 3.Kb1 Rg1 4.Rc1 h1Q 5.Rxg1 Qxg1+ 6.Kb2
  -+  (-9.91)   Depth: 8/21   00:00:00  43kN, tb=26
1...Kd8 2.0-0-0 Rg2 3.Kb1 Rg1 4.Rc1 h1Q 5.Rxg1 Qxg1+ 6.Kb2 Qd4+
  -+  (-9.91)   Depth: 9/22   00:00:00  107kN, tb=54
1...Kd8!
  -+  (-10.19)   Depth: 10/19   00:00:00  197kN, tb=105
1...Kd8--
  -+  (-9.91)   Depth: 11/26   00:00:01  488kN, tb=294
1...Kd8 2.0-0-0 Rg2
  -+  (-9.91)   Depth: 11/26   00:00:01  506kN, tb=336
1...Kd8!
  -+  (-10.19)   Depth: 12/22   00:00:03  1256kN, tb=605
1...Kd8!
  -+  (-10.47)   Depth: 12/23   00:00:03  1282kN, tb=677
1...Kd8!
  -+  (-11.03)   Depth: 12/33   00:00:03  1322kN, tb=760
1...Kd8 2.Ra8+ Kxd7
  -+  (-#18)   Depth: 12/33   00:00:07  2794kN, tb=1288

(Brunjes, MyTown 23.02.2003)

Both of these were run in the Fritz 8 GUI on an Athlon 700 MHz system with 64 MB
of hashtables.

Roy



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.