[gnugo-devel] super-ko violation

[Matthias Krings]

Hi gnugo-list,

The Gnugo-Bot I'm running on KGS managed yesterday to build the tripple 
ko (as black) you can find in the attached sgf. 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.

I do not know whether this problem can be solved via gtp, 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. Even though I 
admit that this is not a very urgent thing to solve...

Matthias

(;GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2]
RU[AGA]SZ[19]HA[6]KM[0.50]TM[600]OT[20/120 Canadian]
PW[peach]PB[yagr]WR[4k]BR[8k]DT[2004-09-13]PC[The Kiseido Go Server (KGS) at 
http://kgs.kiseido.com/]AB[dd][pd][dj][pj][dp][pp]C[yagr [8k\]: GTP Engine for 
yagr (black): GNU Go version 3.6-pre1
]
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