Search found 275 matches

by Fabien Letouzey
Sun Jan 13, 2019 16:53
Forum: Draughts, Computer, Internet
Topic: AMD - Scan 3.0 - Problem
Replies: 18
Views: 3715

Re: AMD - Scan 3.0 - Problem

Hi Krzysztof,
Krzysztof Grzelak wrote:
Sun Jan 13, 2019 14:07
Hi Fabien.
I have such a request for you. Can you help me set up Scan 3.0 for the tournament. My equipment is:
...
I am guessing that you are referring to the number of threads. Let's try 8; in any case you should never use more than that (I only have 4).

Fabien.
by Fabien Letouzey
Wed Nov 21, 2018 07:44
Forum: Draughts, Computer, Internet
Topic: DXP Scan
Replies: 4
Views: 1367

Re: DXP Scan

Thank you for your answer Fabien. I have such an important question. Please write whether Scan 2.0 and 3.0 have a book 2move ballots and 3move ballots. I'm going to think about this question. Like you, Fabian, you tested both versions with each other. Scan does not support move ballots. You can org...
by Fabien Letouzey
Mon Nov 19, 2018 08:03
Forum: Draughts, Computer, Internet
Topic: DXP Scan
Replies: 4
Views: 1367

Re: DXP Scan

I have a question. How to play a dxp game consisting of 158 games using the Scan 2.0 and Scan 3.0. I thank you in advance for all the information. Hi Krzysztof, As far as I know, you can't. But it's important to know why, and I explain it below. What you can do, however, is to use random book moves...
by Fabien Letouzey
Wed Jul 04, 2018 07:43
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

Fabien is right: for a computer constructing proof games seems quite hard. In my program, I do check for illegal position in the constructor (see: http://laatste.info/bb3/viewtopic.php?t=7693) but only for immediate conflicts (overlapping squares or men on the promotion line). The indirect conflict...
by Fabien Letouzey
Mon Jul 02, 2018 10:09
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

I agree with the other criteria, but not this one. Draughts programs are not just used for games, but also to check composed positions for correctness (that's the main usage for me at least). And a composed position can have more than 20 pieces of one side. That certainly seems arbitrary, but older...
by Fabien Letouzey
Mon Jul 02, 2018 08:57
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

Hi Gérard, Should my quesion have concerned non legal position I would have begun by showing the following quite simple position http://fmjd.org/dias2/save/15304635986.png 128 moves You are playing with words. For me the "obvious" properties that a position must have are: - at most one piece on a gi...
by Fabien Letouzey
Sun Jul 01, 2018 18:22
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

Oops if you accept illegal positions then, the position with the maximum moves in a context of men positions (no kings) is not a position with captures but simply the obvious following one :P : ... 45 moves It looks like we're having two conversations with no connections so let me clarify. In this ...
by Fabien Letouzey
Sat Jun 30, 2018 08:23
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

Hi Gérard, BTW in the following position http://fmjd.org/dias2/save/15302706721.png you can count 26 capture moves but this position is not legal is it? This one with a nice symmetry: 28 moves: https://toernooibase.kndb.nl/applet/oerterpapplet2.0/createdia2.php?fen=W:W8,26,30,48:B11,12,13,14,21,22,2...
by Fabien Letouzey
Wed Jun 27, 2018 08:38
Forum: Draughts, Computer, Internet
Topic: Internet engine matches
Replies: 395
Views: 126439

Re: Internet engine matches

Hi Krzysztof, Kingsrow 1.60 vs. Scan 3.0 0 wins, 0 losses, 158 draws, 0 unknowns Is that the first time that a match ends with 100% draws? :) Anyway, your tests also show what we already knew: the draw rate increases in slower games. So 2-move ballots are already too small for top programs. Fabien.
by Fabien Letouzey
Wed Jun 27, 2018 08:32
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

ildjarn wrote:https://toernooibase.kndb.nl/applet/oer ... 2&size=300
Doesn't seem to support the - for multiple pieces in a row though.
Thanks!

That's OK, it's an optional extension in my program.
by Fabien Letouzey
Mon Jun 25, 2018 15:34
Forum: Draughts, Computer, Internet
Topic: Coding issues
Replies: 10
Views: 2014

Re: Coding issues

Hi Gérard, INT64 x = 0xffffffffffffffff; No matter how many digits you put, this is a (signed) 32-bit literal. You need to append ULL (or ui64 for MS compilers) to extend that. "1 << 32" would fall into the same trap (although the compiler is allowed to do the right thing in this case), etc ... Don'...
by Fabien Letouzey
Tue Jun 19, 2018 13:04
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

Unfortunetly I do not know an efficient algorithm to verify if a position is legal or not and my verification is only manual! No problem: you can be step 4, then. 2 kings: 174 W:WK2,K3:B10,14,18,19,28,29,32,34,37,40,41 3 kings: 180 W:WK26,K36,K48:B10,11,14,17,19,22,23,32,33,39,44 191 W:WK25,K35,K49...
by Fabien Letouzey
Tue Jun 19, 2018 12:30
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

Why do you put white kings on 2 and 15? The algorithm is the classical "generate and test". In my case: 1) pick the number of kings and place them at random 2) pick the number of men and place them at random (with constraints) 3) count the number of moves I will add a clean-up phase that removes us...
by Fabien Letouzey
Tue Jun 19, 2018 12:26
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

Let me try a first proposal with legal positions http://fmjd.org/dias2/save/15293994534.png 174 moves If I only allow the cross pattern, I get 225 with 6 kings: W:WK1-3,K6,K16,K26:B10,14,19,22,23,32,33,37,39,41,44 If you want something better, just post an efficient algorithm for legality test, and...
by Fabien Letouzey
Tue Jun 19, 2018 10:58
Forum: Draughts, Computer, Internet
Topic: maximum niumber of legal moves
Replies: 37
Views: 5700

Re: maximum niumber of legal moves

I only said 3-4 kings because exhaustive enumeration becomes too expensive for up to 18 kings :) For random generation, you can go much further. I see. Random search suggests around 8 kings and 14 men; that seems nearly the worst case for exhaustive search: about half of the available squares (old ...