Ya, I agree with you all. In fact, four-move cycle is just a basic type of superko, see
http://senseis.xmp.net/?Cycle I never managed to prohibit moves that form a cycle of length over six. because I thought cases other than triple ko might occur rarely. But it might be worth a try to handle superko with a hash table, though it might be slow. Aja 2012/6/6 Mark Boon <[email protected]> > On Wed, Jun 6, 2012 at 1:47 PM, Darren Cook <[email protected]> wrote: > > > > Is four moves the longest super-ko cycle possible? I thought it could be > > longer, using some capture and refill approach. But I could be very > > wrong on that. > > > > Darren > > > > P.S. Well if the bots are psychotic, and because tromp-taylor rules > > allow suicide, then of course very long cycles are possible, with one > > player always passing, and the other player filling in the same large > > eye over and over... > > My question is more: is a very long cycle possible in a game where both > > players are playing to win? > > > > Four is not the longest, even when you try to win. Quadruple ko takes > eight moves to cycle back. Although not common, it can happen. I had > it happen in a game in the Dutch championship many years ago. > Participation in the World Championship in Japan was on the line, so I > can assure you we were both trying to win. Whether it was ideal play > to let it happen, that's another question altogether... > > I don't know what the longest 'reasonable' cycle would be, but I've > learned not to put my estimates too low with this type of thing in Go. > Before you know it, someone comes up with a 'reasonable' cycle of > longer length than you can count. > > Mark > _______________________________________________ > Computer-go mailing list > [email protected] > http://dvandva.org/cgi-bin/mailman/listinfo/computer-go >
_______________________________________________ Computer-go mailing list [email protected] http://dvandva.org/cgi-bin/mailman/listinfo/computer-go
