Author: Bernhard Bauer
Date: 04:03:42 04/27/99
Go up one level in this thread
On April 27, 1999 at 05:03:34, blass uri wrote:
>
>On April 27, 1999 at 04:09:08, Harald Faber wrote:
>
>>On April 26, 1999 at 23:48:50, Igor Syry wrote:
>>
>>>Hoped you enjoyed the problem...
>>>Igor
>>
>>Yes, I did. I also enjoyed this problem:
>>
>>qnb5/1p1kBK2/pPp5/P1p5/2P5/8/8/8 b - - 0 0
>>
>>White to move and win. It SHOULD be an easy one, only move#2 and the motive must
>>be found.
>>What amazes me is that Crafty and Fritz5.32 with their deepest search depth
>>don't find the final winning move in move#19 pv. They have only a draw eval
>
It's white to move, so the FEN should be
qnb5/1p1kBK2/pPp5/P1p5/2P5/8/8/8 w
>It is not surprising because it is a null move problem.
Indeed. But you can easyly configure crafty *not* to do a null move search.
Then crafty will solve the above position in a second.
Here some output from crafty:
time surplus 0.00 time limit 60:00 (60:00)
depth time score variation (1)
starting thread 1
1 0.11 -12.06 1. Bxc5
1-> 0.12 -12.06 1. Bxc5
2 0.12 -12.00 1. Bxc5 Kd8
2-> 0.14 -12.00 1. Bxc5 Kd8
3 0.14 -11.83 1. Bxc5 Kd8 2. Kg8
3 0.15 ++ 1. Bf8!!
3 0.15 0.00 1. Bf8 Kd8 2. Be7+ Kd7
3-> 0.15 0.00 1. Bf8 Kd8 2. Be7+ Kd7
4 0.17 0.00 1. Bf8 Kd8 2. Be7+ Kd7
4-> 0.17 0.00 1. Bf8 Kd8 2. Be7+ Kd7
5 0.17 0.00 1. Bf8 Kd8 2. Be7+ Kd7
5 0.19 ++ 1. Bg5!!
5 0.19 1.57 1. Bg5 Kd6 2. Bf4+ Kd7 3. Bc7 Qa7 4.
bxa7 Kxc7 5. a8=Q
5 0.20 ++ 1. Bxc5!!
5 0.20 6.18 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. a8=Q
5-> 0.22 6.18 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. a8=Q
6 0.22 ++ 1. Bxc5!!
6 0.23 8.33 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 b6 5. axb8=Q bxa5
6-> 0.25 8.33 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 b6 5. axb8=Q bxa5
7 0.26 ++ 1. Bxc5!!
7 0.28 9.47 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q
7-> 0.33 9.47 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q
8 0.37 9.63 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q Kd8
8-> 0.47 9.63 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q Kd8
9 0.48 ++ 1. Bxc5!!
9 0.69 Mat07 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q Kd8
7. Qc7#
9-> 0.90 Mat07 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q Kd8
7. Qc7#
time=0.90 cpu=2049% mat=-14 n=168812 fh=99% nps=185507
ext-> checks=9535 recaps=512 pawns=3374 1rep=1090 thrt:0
predicted=0 nodes=168812 evals=564
endgame tablebase-> probes done=0 successful=0
SMP-> split=447 stop=17 data=6/64 cpu=18.65 elap=0.91
mate in 7 moves.
This version of crafty may not play very good because null move helps a lot.
But you may configure crafty in a way that it will normally use the null move
search, but not when there is low material on the board. Such a version gives:
starting thread 1
1 0.10 -12.06 1. Bxc5
1-> 0.11 -12.06 1. Bxc5
2 0.11 -12.00 1. Bxc5 Kd8
2-> 0.11 -12.00 1. Bxc5 Kd8
3 0.13 -11.83 1. Bxc5 Kd8 2. Kg8
3 0.13 ++ 1. Bf8!!
3 0.13 0.00 1. Bf8 Kd8 2. Be7+ Kd7
3-> 0.13 0.00 1. Bf8 Kd8 2. Be7+ Kd7
4 0.14 0.00 1. Bf8 Kd8 2. Be7+ Kd7
4-> 0.14 0.00 1. Bf8 Kd8 2. Be7+ Kd7
5 0.16 0.00 1. Bf8 Kd8 2. Be7+ Kd7
5 0.16 ++ 1. Bg5!!
5 0.16 1.57 1. Bg5 Kd6 2. Bf4+ Kd7 3. Bc7 Qa7 4.
bxa7 Kxc7 5. a8=Q
5 0.17 ++ 1. Bxc5!!
5 0.17 6.18 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. a8=Q
5-> 0.19 6.18 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. a8=Q
6 0.19 ++ 1. Bxc5!!
6 0.21 8.33 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 b6 5. axb8=Q bxa5
6-> 0.22 8.33 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 b6 5. axb8=Q bxa5
7 0.24 ++ 1. Bxc5!!
7 0.28 9.47 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q
7-> 0.33 9.47 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q
8 0.44 9.63 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q Kd8
8-> 0.55 9.63 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q Kd8
9 0.55 ++ 1. Bxc5!!
9-> 0.94 10.02 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q Kd8
10 1.38 -- 1. Bxc5
10 1.41 ++ 1. Bxc5!!
10-> 2.10 10.01 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q Kd8
11 2.11 ++ 1. Bxc5!!
11 3.44 Mat07 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q b6 7.
Qc7#
11-> 4.63 Mat07 1. Bxc5 Kd8 2. Be7+ Kd7 3. c5 Qa7 4.
bxa7 Kc7 5. Bd6+ Kd7 6. axb8=Q b6 7.
Qc7#
time=4.63 cpu=415% mat=-14 n=1208305 fh=99% nps=261537
ext-> checks=62247 recaps=4809 pawns=14553 1rep=4646 thrt:171
predicted=0 nodes=1208305 evals=5100
endgame tablebase-> probes done=0 successful=0
SMP-> split=999 stop=32 data=7/64 cpu=19.19 elap=4.62
mate in 7 moves.
All computation done on a 2XPPro 232 MHz.
>
>If black has the right not to play then white cannot threat the black king at
>d7(the pawns cannot move and the bishop cannot see d7)
>
>
>I suggest that you use better programs like Genius3 for analyzing studies.
>
>Junior is also better in this position but it has practical problems in other
>studies
>(for example when there is under promotion)
>
>Uri
So no need to take Genius, ...
Crafty is very nice and powerfull.
Kudo's to Bob.
Kind regards
Bernhard
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