Talk:Computer Othello

Solve Othello 8 x 8
How long would it take to solve Othello 8 x 8 if it was done as a distributed project over the internet? Would it take less than a year? Mschribr (talk) 21:41, 7 May 2010 (UTC)

An average number of moves is 7. A game has 60 moves. So that's 7^60 leaves in the search tree. That's approximately 1 with 60 zeros, way beyond today's capability. With pruning and other clever ideas, now a program can search 30 moves ahead, but pushing this number further is increasingly hard. A lot of hardware can increase maybe 1 or 2 moves, but a good algorithm can do a lot. Wangzirui (talk) 10:27, 6 November 2010 (UTC)
 * 10^60 is 1 followed by 60 zeros. 7 is less than 10. So 7^60 is less than 1 followed by 60 zeros. 7^60 is about 10^51. However, 7^60 is the number of games. I am asking about weakly solving Othello. This is solving the game only from the start position. We do not need to look at every game or every position. The number of legal positions is 10^28. See game complexity. Checkers was solved and it is 10^20. Therefore, Othello is on order of only 100 million more than Checkers. Distributing it over the internet with today’s faster computers then I think Othello could be weakly solved in a year. Is anybody working on solving Othello? --Mschribr (talk) 12:18, 7 November 2010 (UTC)

Personnaly I think it is feasible within one year on a very fast computer with a strong Othello program. There is no need of distributing it over internet. If game complexity is 10^28, a perfectly ordered alphabeta will visit only 10^14 nodes to solve it. Current computer othello programs achieve 10^8 nodes per second. So a fast and perfect Othello program should be able to solve the game in 2 weeks. Of course perfect programs do not exist, and more time may be needed to actually solve Othello, but maybe it is feasible within one year on a very fast computer with a strong othello program. Abulmo (talk) 18:35, 17 November 2010 (UTC)
 * Then why is no one trying to weakly solve Othello? It is a popular game. Mschribr (talk) 18:58, 18 November 2010 (UTC)
 * Well I am trying to solve it (http://abulmo.perso.neuf.fr/edax/4.0/solving.htm), but my computer is not fast enough (only 4 'true' cores). However, I am still wondering why the game is not solved yet. The game is much less popular than chess or go, and programs are much stronger than humans since a long time, so there is probably less interest in Othello than in other games now. Abulmo (talk) 15:29, 27 March 2012 (UTC)

Link Problems
All of the links at the bottom of this page to the top programs are misdirects, with the exception of NTest. Reality Bent (talk) 21:03, 1 October 2010 (UTC)

8x8 Othello Programs Comparison
_____________Evaluation Speed Book

1. NTest. . . . 10.0 . . . 9.0 . .9.5

2. Saio. . . . . 9.5 . . .10.0 . 10.0

3. Edax. . . . . 9.0 . . .10.0 . 10.0

4. Cassio. . . . 9.0 . . .10.0 . 10.0

5. WZebra. . . . 8.0 . . . 8.0 . .8.0

NTest's evaluation function and accuracy is the highest, the opening book is smaller - because only contain perfect play positions, the program speed is slower - it has not been updated since 2005. — Preceding unsigned comment added by 114.79.12.188 (talk) 15:14, 19 February 2012 (UTC)


 * The above table is very subjective, not to say completely wrong. First Cassio is strong (stronger than Zebra) only when it uses Edax or Cyrano as its brain and avoid using its own. Cassio is a wonderful program, probably with the best GUI, but not that strong by itself. More generally, it is very hard to compare Othello programs. The only source are games played on internet (on the Generic Game Server, aka GGS, developed by Michael Buro & Igor Durdanovich), with programs running on computer of different strengths, programs evolving, having surname (piglet = logistello, Reindeer = WZebra, s26 = ntest = Ntest, etc.). From those games, it is hard to see any difference between Ntest, WZebra and Logistello. I compute some ELO rating lists here : (http://abulmo.perso.neuf.fr/rating/2010.htm and http://abulmo.perso.neuf.fr/rating/2010.htm). In 2009 WZebra > NTest > Logistello, but not in a significant way. In 2010 Logistello > Ntest > WZebra, no more significantly, with no real change in computers running them. Personnaly, I will not dare to say which program is the strongest now. Abulmo (talk) 16:04, 27 March 2012 (UTC)

Saio, Edax, and Cassio is now the fastest top programs. Most made othello programs are 8x8 board size, while Herakles is the strongest 10x10 othello program (since April 2002), and also Tothello is the strongest 4x4 and 6x6 othello program (since July 2006). There are othello programs that provide larger board size such as 12x12 size, but they are all much weaker compared to top human players, they are not made optimized to be as strong as the above top programs listed. — Preceding unsigned comment added by 114.79.12.11 (talk) 11:17, 29 February 2012 (UTC)

Daisy Reversi is a strong program, but not strong enough against some human top players. However, since this program has no rival programs particularly in larger board size gameplay, this program has became the strongest othello 12x12, 14x14, 16x16, 18x18, 20x20, 22x22 and 24x24 program. — Preceding unsigned comment added by 114.79.12.80 (talk) 08:34, 4 March 2012 (UTC)

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MIcrosoft Windows 3.0, XP, ME
Reversi was included into the games of [Windows 3.0]] and also belonged to the internet games of Windows XP and Windows ME. {https://microsoft.fandom.com/wiki/Reversi] --87.162.173.197 (talk) 23:54, 16 May 2020 (UTC)