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Subject: Re: Which engines can solve this? (Crafty 19.08)

Author: Mike Byrne

Date: 08:15:37 01/11/04

Go up one level in this thread


On January 11, 2004 at 10:28:29, Uri Blass wrote:

>On January 11, 2004 at 09:08:55, Mike Byrne wrote:
>
>>On January 11, 2004 at 02:46:18, Uri Blass wrote:
>>
>>>On January 11, 2004 at 00:07:22, Mike Byrne wrote:
>>>
>>>>On January 10, 2004 at 20:23:32, Bob Durrett wrote:
>>>>
>>>>>On January 10, 2004 at 18:29:20, Mike Byrne wrote:
>>>>>
>>>>>>On January 10, 2004 at 17:47:25, Drexel,Michael wrote:
>>>>>>
>>>>>>>On January 10, 2004 at 17:22:53, Kurt Utzinger wrote:
>>>>>>>
>>>>>>>>On January 10, 2004 at 15:29:16, David Dahlem wrote:
>>>>>>>>
>>>>>>>>>White to move and draw. Which engines can find it?
>>>>>>>>>
>>>>>>>>>[D]3B4/1r2p3/r2p1p2/bkp1P1p1/1p1P1PPp/p1P1K2P/PPB5/8 w - - 0 1
>>>>>>>>>
>>>>>>>>>1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6. f5 1/2-1/2
>>>>>>>>>
>>>>>>>>>Regards
>>>>>>>>>Dave
>>>>>>>>
>>>>>>>>Crafty_1908  WB2: (P4 1.8/32 MB hash)
>>>>>>>> 3   00:00 -4.04   1. c4+ Kxc4 2. Bd3+ Kd5 3. Bxa6 cxd4+ 4. Kd3
>>>>>>>> 4   00:00 -4.01   1. c4+ Kxc4 2. Bd3+ Kd5 3. Bxa6 cxd4+ 4. Kd3 Ra7
>>>>>>>> 4   00:00 -3.64   1. Ba4+!!
>>>>>>>> 4   00:00  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5
>>>>>>>> 5   00:00  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5 Rba7
>>>>>>>> 6   00:00  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5 Rba7 7. Kf3
>>>>>>>> 7   00:01  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5 Rba7 7. Kf3 Rc6
>>>>>>>> 8   00:01  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5 Rba7 7. Kf3 Rc6 8. Ke4
>>>>>>>> 9   00:01  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5 Rba7 7. Kf3 Rc6 8. Ke4 Rb6
>>>>>>>>10   00:03  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5 Rba7 7. Kf3 Rc6 8. Ke4 Rb6 9. Kf3
>>>>>>>>11   00:08  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5 Rba7 7. Kf3 Rc6 8. Ke4 Rb6 9. Kf3 Rc6
>>>>>>>>12   00:11  0.00   1. Ba4+ Kxa4 2. b3+ Kb5 3. c4+ Kc6 4. d5+ Kd7 5. e6+ Kxd8 6.
>>>>>>>>f5 Rba7 7. Kf3 Rc6 8. Ke4 Rb6 9. Kf3 Rc6
>>>>>>>
>>>>>>>Interesting. Crafty 19.06 can't find 1.Ba4+.
>>>>>>>
>>>>>>>Michael
>>>>>>>
>>>>>>>New game
>>>>>>>3B4/1r2p3/r2p1p2/bkp1P1p1/1p1P1PPp/p1P1K2P/PPB5/8 w - - 0 1
>>>>>>>
>>>>>>>Analysis by Crafty 19.06:
>>>>>>>
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Bxa6 cxd4+
>>>>>>>  -+  (-4.45)   Depth: 1/18   00:00:00
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Bxa6 cxd4+
>>>>>>>  -+  (-4.45)   Depth: 1/18   00:00:00
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Bxa6 cxd4+
>>>>>>>  -+  (-4.45)   Depth: 2/18   00:00:00
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Bxa6 cxd4+
>>>>>>>  -+  (-4.45)   Depth: 2/18   00:00:00
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Bxa6 cxd4+
>>>>>>>  -+  (-4.45)   Depth: 2/18   00:00:00
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Bxa6 cxd4+ 4.Kd3
>>>>>>>  -+  (-4.28)   Depth: 3/19   00:00:00
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Bxa6 cxd4+ 4.Kd3 Ra7
>>>>>>>  -+  (-4.25)   Depth: 4/19   00:00:00
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Be4+ Ke6 4.f5+ Kd7 5.Bxb7 axb2 6.Bxa6 b1Q 7.Bxa5 dxe5
>>>>>>>8.dxc5 Qxa2
>>>>>>>  -+  (-5.36)   Depth: 5/23   00:00:00
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Be4+ Ke6 4.f5+ Kd7 5.Bxb7 axb2 6.Bxa6 b1Q 7.Bxa5 dxe5
>>>>>>>8.dxc5 Qxa2
>>>>>>>  -+  (-5.36)   Depth: 6/24   00:00:00  392kN
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Be4+ Ke6 4.f5+ Kd7 5.Bxb7 axb2 6.Bxa6 b1Q 7.Bxa5 dxe5
>>>>>>>8.dxc5 Qxa2
>>>>>>>  -+  (-5.36)   Depth: 7/26   00:00:01  806kN
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Be4+ Ke6 4.Bxb7 gxf4+ 5.Kxf4 dxe5+ 6.dxe5 Ra7 7.Bxa5
>>>>>>>axb2 8.Bc8+ Kd5 9.Bb6 b1Q 10.Bxa7 Qxa2
>>>>>>>  -+  (-5.73)   Depth: 8/27   00:00:04  2236kN
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Be4+ Ke6 4.f5+ Kd7 5.Bxb7 cxd4+ 6.Kxd4 dxe5+ 7.Kc5 Ra7
>>>>>>>8.bxa3 Bxd8 9.Bc6+ Kc7 10.axb4 Rxa2
>>>>>>>  -+  (-6.00)   Depth: 9/28   00:00:08  5405kN
>>>>>>>1.c4+ Kxc4 2.Bd3+ Kd5 3.Be4+ Ke6 4.f5+ Kf7 5.Bxb7 axb2 6.Bxa6 b1Q 7.Bxa5 Qxa2
>>>>>>>8.e6+ Kf8 9.Bb6 Qxa6 10.dxc5 dxc5 11.Bxc5
>>>>>>>  -+  (-6.55)   Depth: 10/30   00:00:31  21256kN
>>>>>>
>>>>>>It becomes a block pawn position, so when crafty is compiled with /DDETECTDRAW,
>>>>>>it will find it.
>>>>>
>>>>>Would somebody who is familiar with Crafty's /DDETECTDRAW code please tell
>>>>>everybody WHY is works [in plain English, please]?  What is special about that
>>>>>code which almost every other chess programmer has failed to put into his/her
>>>>>engines?  What does that code do [other than produce the correct move] which is
>>>>>unique?
>>>>>
>>>>>Bob D.
>>>>
>>>>A picture is worth a thousand words, play the best moves for the above position
>>>>and take a look at the ending position.
>>>>
>>>>[d]3k4/1r2p3/r2pPp2/b1pP1Pp1/1pP3Pp/pP2K2P/P7/8 b - - 0 6
>>>>
>>>>the code simply identifies a locked position where the K is safely behind bars
>>>>(pawns) , i.e., the game must be drawn.
>>>
>>>The question is if it does not detect draw in wrong cases(for example if black
>>>has a queen instead of a bishop.
>>>
>>>Uri
>>
>>
>>New game
>>3k4/1r2p3/r2pPp2/q1pP1Pp1/1pP3Pp/pP2K2P/P7/8 b - - 0 1
>>
>>Analysis by Crafty 19.08 SE:
>>
>>6...Qa4 7.bxa4 b3 8.axb3 Rxb3+ 9.Ke4 Rxh3 10.a5 Rxa5
>>  -+  (-23.39)   Depth: 8   00:00:00  101kN
>>6...Qa4
>>  -+  (-23.79)   Depth: 9   00:00:00  112kN
>>6...Qa4 7.bxa4 b3 8.axb3 Rxb3+ 9.Ke4 Rxh3 10.a5 Rh1 11.Kd3 Rxa5
>>  -+  (-23.89)   Depth: 9   00:00:00  114kN
>>6...Qa4 7.bxa4 b3 8.axb3 Rxb3+ 9.Ke4 Rxh3 10.a5 Rh1 11.Kd3 Rxa5
>>  -+  (-23.89)   Depth: 9   00:00:00  255kN
>>6...Qa4 7.bxa4 b3 8.axb3 Rxb3+ 9.Ke4 Rxh3 10.a5 Rh1 11.Kf3 Rxa5
>>  -+  (-23.99)   Depth: 10   00:00:00  285kN
>>6...Qa4 7.bxa4 b3 8.axb3 Rxb3+ 9.Ke4 Rxh3 10.a5 Rh1 11.Kf3 Rxa5
>>  -+  (-23.99)   Depth: 10   00:00:01  566kN
>>6...Qa4
>>  -+  (-24.39)   Depth: 11   00:00:01  573kN
>>6...Qa4 7.bxa4 b3 8.axb3 Rxb3+ 9.Kf2 Rab6 10.Ke2 Rb2+ 11.Kf3 R6b3+ 12.Ke4 Re2#
>>  -+  (-#7)   Depth: 11   00:00:11  6025kN
>>6...Qa4 7.bxa4 b3 8.axb3 Rxb3+ 9.Kf2 Rab6 10.Ke2 Rb2+ 11.Kf3 R6b3+ 12.Ke4 Re2#
>>  -+  (-#7)   Depth: 11   00:00:13  7559kN
>>6...Qa4 7.bxa4 b3 8.axb3 Rxb3+ 9.Kf2 Rab6 10.Ke2 Rb2+ 11.Kf3 R6b3+ 12.Ke4 Re2#
>>  -+  (-#7)   Depth: 12   00:00:50  27457kN
>>
>>(Byrne, Secane, PA USA 11.01.2004)
>>
>>not in this case ..you put any type of piece (Queen, light square bishop or
>>knight) that can a  force a win and it will see it
>
>Of course it is going to see it by search but the question was about static
>evaluation.
>
>You give only analysis at big depth and not at depth 1.
>
>Uri

it needs 3 plies to in search tos ee that it bust through the locked pawns ---
that is how chess programs work ..search and evaluation ..not just one simple
static score at sd 1..



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