Author: Bernhard Bauer
Date: 04:34:46 10/13/98
Go up one level in this thread
On October 13, 1998 at 06:05:55, blass uri wrote:
>
>On October 13, 1998 at 05:54:00, blass uri wrote:
>
>>
>>On October 13, 1998 at 04:34:00, Amir Ban wrote:
>>
>>>On October 13, 1998 at 02:12:24, Jouni Uski wrote:
>>>
>>>>In SSDF game archive there is 5834 games. In 21 games there is KQ-KR ending.
>>>>And 20 of these were won by Q side WITHOUT any use of TBs! Quite surprising -
>>>>isn't this normally considered as difficult ending?
>>>
>>>I've never seen this ending in a computer-computer game where the side with the
>>>queen failed to win, at any time control.
>>>
>>>This endgame is quite easy for a computer.
>>
>>Is it easy when the defendor use tablebases?
>>
>>I found that the defendor without tablebases(when the defendor is a computer
>>program) may miss a simple draw by perpetual check in positions when there is
>>black queen at f2 and white king at h1.
>
>Here is an example
>
>7R/8/8/8/8/k7/5q2/7K white to move and draw
>Fritz5(without tablebases) plays Rg8 and Junior5(16 bit) Rh3+
>when Ra8+ is the only way to draw.
>
>Uri
>
Crafty 15.20 finds the draw without tablebases.
On a 2xPPro 233MHz crafty sees Ra8+ at ply 14 in 2:48 min.
Crafty sees the draw (score =-0.66) at ply 23 in 3:45 min.
The output for ply 42 is:
42-> 8:04 -0.66 1. Ra8+ Kb3 2. Rb8+ Kc3 3. Rc8+ Kd3
4. Rd8+ Ke3 5. Re8+ Kd4 6. Rd8+ Ke4
7. Re8+ Kd5 8. Rd8+ Kc4 9. Rc8+ Kb4
10. Rb8+ Ka4 11. Ra8+ Kb5 12. Rb8+
Ka5 13. Ra8+ Kb6 14. Rb8+ Kc5 15. Rc8+
Kd6 16. Rd8+ Kc6 17. Rc8+ Kd7 18. Rd8+
Ke6 19. Re8+ Kd5
Kind regards
Bernhard
>
>>
>>Uri
>>>
>>>Amir
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.