Search found 1638 matches

by Rein Halbersma
Mon Oct 09, 2017 12:32
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 52603

Re: Breakthrough Draughts

Hi Michel, Good news to see your interesting by this beautitul draughts variant. As with Bert I have the same difficulty with you : I did not generate the capture positions. Bert managed to add statitistics on non capture position in order to compare our figures but I do not know if it is easy for ...
by Rein Halbersma
Thu Sep 28, 2017 21:05
Forum: Draughts, Computer, Internet
Topic: Internet engine matches
Replies: 450
Views: 153415

Re: Internet engine matches

To all involved, it is and was my intention to share much in this forum. And openly discuss all I'm working on, and also provide lots of source code. As apparently I'm a liar, I conclude that my contribution is not valued, and I considered this my last post in this forum. Good luck to all. Bert Ber...
by Rein Halbersma
Thu Sep 28, 2017 15:28
Forum: Draughts, Computer, Internet
Topic: Internet engine matches
Replies: 450
Views: 153415

Re: Internet engine matches

I fully agree with you Krzysztof , the most important point is winning! 10 or 20 years ago the best programs were not so strong and we observed a lot of winning games. Unfortunately my feeling is that draughts is really a drawing game : during a high level game I think that almost all positions enc...
by Rein Halbersma
Thu Sep 21, 2017 07:23
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 52603

Re: Breakthrough Draughts

Gerard's reasoning was first made in 1981 as a statistical property of game trees. Citing Uiterwijk and Van den Herik (2000, see http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.109.3661): In 1981, David Singmaster [25,26] proved a rather conclusive and elegant theorem why first-player wins s...
by Rein Halbersma
Fri Sep 15, 2017 00:37
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 52603

Re: Breakthrough Draughts

If a program is specifcally built to solve the starting game position then I can see a significant difference between "weakly solved" and "strongly solved". In the case here the db built covers all positions with 16 pieces or less, and youcan note that most of these positions are not reachable from...
by Rein Halbersma
Thu Sep 14, 2017 23:50
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 52603

Re: Breakthrough Draughts

Gerard, I think we could call it weakly solved (but think Rein has the final verdict). So far no other moves other than 23-19 which have a final score. I will also go towards 15P and 16P, but not immediately to 10x10 BT. I want to do some other tests first. If the 2018 Computer Olympics is again in...
by Rein Halbersma
Sat Sep 02, 2017 17:09
Forum: Draughts, Computer, Internet
Topic: Complexity of Checkers and Draughts on board sizes 6x6/8x8/10x10/12x12/14x14
Replies: 11
Views: 10183

Re: Complexity of Checkers and Draughts on board sizes 6x6/8x8/10x10/12x12/14x14

14x14 4969247364259229765636136727875248396725305632355107910329548406783 = 5.0 x 10^66 For 14x14 I cannot confirm this. I just got a PM from the author of this post on talkchess: http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=680216&t=27814 We both find 7.71788e+66 instead of 5.0e+6...
by Rein Halbersma
Sat Sep 02, 2017 14:25
Forum: Draughts, Computer, Internet
Topic: Complexity of Checkers and Draughts on board sizes 6x6/8x8/10x10/12x12/14x14
Replies: 11
Views: 10183

Re: Complexity of Checkers and Draughts on board sizes 6x6/8x8/10x10/12x12/14x14

Applying this formula on the 5 board formats, we obtain (for 1 color to move): Board size SSC <= 6x6 63838220543 = 6.4 x 10^10 8x8 500995484682338672639 = 5.0 x 10^20 [1] 10x10 2301985676687843186738387267616767 = 2.3 x 10^33 12x12 5732895173337388545809530684864049716501476802559 = 5.7 x 10^48 14x...
by Rein Halbersma
Fri Sep 01, 2017 14:00
Forum: het Nieuwe Forum
Topic: Eindspeltheorie bij Damclub Den Haag
Replies: 7
Views: 5233

Re: Eindspeltheorie bij Damclub Den Haag

Goed initiatief. Ik zou je alleen wel aanbevelen om Kingsrow met de 7 en 8 stukken databases aan te schaffen. Bij het naspelen van Leclerq-2 kwam ik al een aantal onnauwkeurigheden op het spoor. http://fmjd.org/dias2/save/15042670072.png Zaz speelt niet 37-41? 48-31! (tekst) of 14-20? (motief) maar ...
by Rein Halbersma
Wed Aug 30, 2017 19:25
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 52603

Re: Breakthrough Draughts

Hi Bert, Did you developped a perft founction for 8x8 breakthrough game? I did but, due to my special format of the positions, and doubt we can easliy exchange on that point. This is what I get for 8x8 breakthrough draughts. The first 7 ply are identical to normal 8x8 draughts. perft(13) 2387390847...
by Rein Halbersma
Sat Aug 26, 2017 11:59
Forum: Draughts, Computer, Internet
Topic: Perft
Replies: 248
Views: 106735

Re: Perft

I noticed that Harm, Ed, and you use these ray masks for king jumps Rein, I implemented the ray mask while studying the Moby Dam code from Harm. I thought this was a very clever approach, and therefore also implemented this. So all credits to him. Bert Yes, Harm's program is a great piece of work. ...
by Rein Halbersma
Sat Aug 26, 2017 11:45
Forum: Draughts, Computer, Internet
Topic: Perft
Replies: 248
Views: 106735

Re: Perft

Rein, 8 core Intel, 4 GHz. Attached the source, so all may use, or propose improvements. Bert I noticed that Harm, Ed, and you use these ray masks for king jumps. It took me a long time to fully understand how they work, but they are very clever! However, because the ray masks are of constant lengt...
by Rein Halbersma
Sat Aug 26, 2017 10:40
Forum: Draughts, Computer, Internet
Topic: Perft
Replies: 248
Views: 106735

Re: Perft

A weekend in Holland. Full bulk counting, but should still be a little beter :D Perft(11) N = 1665861398 7.35 sec. KN/sec = 226647 Perft(9) N = 1216917193 3.95 sec. KN/sec = 308080 Perft(15) N = 346184885 2.38 sec. KN/sec = 145455 Bert What are your machine specs, Bert? My latest results: Ubuntu Li...
by Rein Halbersma
Wed Aug 23, 2017 22:26
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 52603

Re: Breakthrough Draughts

So when I Verify all 13P and 14P, I really need to find some speed improvements, otherwise I will never create a 24P DB. Bert Bert, you are no doubt doing this already, but just in case: do you generate the indices in the following order? Index 0 has white pieces on squares 6, 7, 8... etc., and for...
by Rein Halbersma
Wed Aug 23, 2017 20:03
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 52603

Re: Breakthrough Draughts

It is a little difficult to determine the exact cause of the error but I am convinced it is due to the ast coding error I found. It looks like: UINT32 number1 = 98280; UINT32 number2 = 376740; UINT64 number3 = number1 * number2; and my compiler gives a wrong result I should have written UINT64 numb...