Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Eureka! Voila! Ooh La La! (Thanks Uri!)

Author: Reinhard Scharnagl

Date: 04:22:01 12/04/05

Go up one level in this thread


On December 04, 2005 at 07:15:34, Uri Blass wrote:

>On December 04, 2005 at 07:01:41, Reinhard Scharnagl wrote:
>
>>On December 04, 2005 at 06:54:09, Uri Blass wrote:
>>
>>>On December 04, 2005 at 06:43:01, Reinhard Scharnagl wrote:
>>>
>>>>On December 04, 2005 at 06:35:35, Uri Blass wrote:
>>>>
>>>>>I do not know about double checks when a piece that moved does not give check.
>>>>
>>>>Hi Uri,
>>>>
>>>>[D]8/8/3k4/2pP4/8/B2R4/4K3/8 w - c6 0 1
>>>>
>>>>I just composed that. Watch the Pawn e.p. capture move.
>>>>
>>>>Reinhard.
>>>
>>>Hi Reinhard,
>>>Thanks I see it now.
>>[D]>
>>>It seems that enpassent is the only case that it can happen and it can only
>>>happen from rook a1-a8 direction and diagnol direction.
>>>I thought about enpassent capture earlier but not about this example but about
>>>checks from h5-a5 direction.
>>>
>>>Fortunately this example does not lead to a bug in movei.
>>>I had in the past a bug when I assumed that checks cannot be done from 2 rook
>>>directions but calculating the direction of checks after a move is not done
>>>based on the previous move.
>>
>>Hi Uri,
>>
>>e.p. could be strange. See that e.p. is impossible, PINNED through two pieces at
>>
>>[D]8/1k6/8/1KpP1r2/8/8/8/8 w - c6 0 1
>>
>>Reinhard.
>
>Hi Reinhard,
>I know this idea.
>
>see the last diagram in
>http://homepages.caverock.net.nz/~peter/perft.htm that is about the same idea
>when 1.g4 fxg3 or 1.e4 fxe3 or 1.e4 c5 2.bxc6 are illegal

Well Uri,

I know, because SMIRF stands the test

FEN: 8/2p5/3p4/KP5r/1R3p1k/8/4P1P1/8 w - - 0 1

  +-a--b--c--d--e--f--g--h-+ MS Vis.Studio C++ Vers. 13.10
8 |   :::   :::   :::   :::| (Compilation: Dec  4 2005)
7 |:::   [p]   :::   :::   |
6 |   :::   [p]   :::   :::| Perft Testseries
5 |<K><P>:::   :::   :::[r]| (With TT Caching 256.0 MB / 4-fold)
4 |   <R>   :::   [p]   [k]| TT Access Success 65.6%
3 |:::   :::   :::   :::   |
2 |   :::   :::<P>:::<P>:::| Smirf Test No.: 03
1 |:::   :::   :::   :::   |
=>+-a--b--c--d--e--f--g--h-+ Break Time 133.0 Sec.

Ply      Nodes     all (x)     (e.p.)     all (+)      (#)      Prom.Castl. Sec.
--------------------------------------------------------------------------------
1           14           1          0           2        0          0     0    0
2          191          14          0          10        0          0     0    0
3         2812         209          2         267        0          0     0    0
4        43238        3348        123        1680       17          0     0    0
5       674624       52051       1165       52950        0          0     0    0
6     11030083      940350      33325      452473     2733       7552     0  0.2
7    178633661    14519036     294874    12797406       87     140024     0  1.4
8   3009794393   267586558    8009239   135626805   450410    6578076     0  8.2
9  50086749815  4208748290   73050803  3440345177    42191  126512072     0 46.7
0 860322602309 77713272174 1925918820 41928658205 81628976 3712673376     0337.2
--------------------------------------------------------------------------------

Reinhard.



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.