[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [gnugo-devel] super-ko violation
From: |
Gunnar Farnebäck |
Subject: |
Re: [gnugo-devel] super-ko violation |
Date: |
Wed, 15 Sep 2004 01:36:04 +0200 |
User-agent: |
EMH/1.14.1 SEMI/1.14.3 (Ushinoya) FLIM/1.14.2 (Yagi-Nishiguchi) APEL/10.3 Emacs/21.3 (sparc-sun-solaris2.9) MULE/5.0 (SAKAKI) |
Matthias wrote:
> The Gnugo-Bot I'm running on KGS managed yesterday to build the
> tripple ko (as black) you can find in the attached sgf.
Indeed, a genuine triple-ko.
> It seems, that Gnugo (3.6-pre1) violated the super-ko rule.
> Unfortunately I do not have the exact position, where this happened
> (some moves are missing at the end of the file saved on KGS). I
> reconstruced the moves starting with M1, and verified that gnugo
> would play in the position at the end of the attached file L6, which
> violates super-ko. KGS reported (in my log files) that the illegal
> move L6 was send from the engine, so I suppose this was indeed what
> happened.
Seems reasonable.
> I do not know whether this problem can be solved via gtp,
It cannot.
> but at least I wanted to let you know that this problem exists. And
> even if it is not possible to communicate the exact rules which are
> used, gnugo has to deal with a super-ko situation in one way or
> another.
There's a long-standing TODO item to implement superko detection. For
this particular position it may also be worth adding some test cases
about the moves leading up to the triple-ko.
> Even though I admit that this is not a very urgent thing to
> solve...
Well, the fact that we now have an example of a game leading to
triple-ko may increase the motivation to implement superko detection.
/Gunnar