Author: Robert Hyatt
Date: 12:47:26 03/07/06
Go up one level in this thread
On March 07, 2006 at 14:13:48, Uri Blass wrote:
>On March 07, 2006 at 10:39:40, Will Singleton wrote:
>
>>On March 07, 2006 at 03:33:12, Richard Pijl wrote:
>>
>>>On March 06, 2006 at 22:53:05, Dann Corbit wrote:
>>>
>>>>Lot's of programs have a problem with this one. It's a sacrifice leading to a
>>>>forced mate. I would not worry about this one too much:
>>>>[D] 4r1k1/p1qr1p2/2pb1Bp1/1p5p/3P1n1R/1B3P2/PP3PK1/2Q4R w - - bm Qxf4
>>>
>>>Single reply extensions, mate threat extensions and checks in quiescense search
>>>all help in finding this one quickly. Down-side: When used unrestricted,
>>>searches will explode. I agree here with Dann, don't worry about this one.
>>>The Baron finds the move in 7.6 seconds on a Xeon 2.8, reporting the mate in 48
>>>seconds.
>>>
>>> ply time nodes score pv
>>> 2( 3)- 0:00.00 285 -1.23 Kg2-g1 (Re8-e2)
>>> 2( 3)& 0:00.00 383 -1.70 Kg2-f1 Kg8-f8
>>> 2( 3). 0:00.00 414 -1.70 Kg2-f1 Kg8-f8
>>> 3( 5)& 0:00.00 757 -1.44 Kg2-f1 Kg8-f8 Qc1-d2
>>> 3( 5). 0:00.00 903 -1.44 Kg2-f1 Kg8-f8 Qc1-d2
>>> 4( 7)& 0:00.02 2352 -1.58 Kg2-f1 Kg8-f8 Bf6-g5 Nf4-e2
>>> 4( 7). 0:00.02 2880 -1.58 Kg2-f1 Kg8-f8 Bf6-g5 Nf4-e2
>>> 5( 9)& 0:00.09 14038 -1.70 Kg2-f1 Re8-e2 Kf1-g1 Re2xf2 Qc1-e1
>>> 5( 9). 0:00.09 15667 -1.70 Kg2-f1 Re8-e2 Kf1-g1 Re2xf2 Qc1-e1
>>> 6(12)& 0:00.28 44250 -1.81 Kg2-f1 Re8-e2 Kf1-g1 Re2xf2 Qc1-e3
>>> Rf2-g2 Kg1-f1 Kg8-h7
>>> 6(12). 0:00.30 48368 -1.81 Kg2-f1 Re8-e2 Kf1-g1 Re2xf2 Qc1-e3
>>> Rf2-g2 Kg1-f1 Kg8-h7
>>> 7(13)& 0:00.97 153287 -1.93 Kg2-f1 Re8-e2 Rh1-h2 Kg8-f8 a2-a4
>>> b5xa4 Bb3xa4 Nf4-d3
>>> 7(13). 0:01.45 232925 -1.93 Kg2-f1 Re8-e2 Rh1-h2 Kg8-f8 a2-a4
>>> b5xa4 Bb3xa4 Nf4-d3
>>> 8(16)+ 0:04.75 784071 -1.58 Kg2-f1 (Re8-e2) (Rh4xf4) (Bd6xf4) (Qc1-b1)
>>>
>>> (Rd7-e7) (Qb1xg6) (Kg8-f8) (Bf6xe7)
>>>(Qc7xe7) (Qg6xf7)
>>> 8(16)& 0:07.05 1186288 -1.03 Kg2-f1 Rd7-e7 Bf6xe7 Re8xe7 Rh1-g1
>>> Kg8-f8 Rg1-g5 f7-f6 Rg5-g3
>>> 8(16)+ 0:07.61 1302604 -0.33 Qc1xf4 (Bd6xf4) (Rh4xh5) (g6xh5) (Rh1xh5)
>>> (Bf4-h6) (Rh5xh6) (Kg8-f8) (Rh6-h8)
>>> 8(17)& 0:47.89 10652406 MATE6 Qc1xf4 Bd6xf4 Rh4xh5 g6xh5 Rh1xh5
>>> Bf4-h6 Rh5xh6 Qc7-h2 Kg2xh2 b5-b4 Rh6-h8
>>> 8(17). 0:48.12 10697945 MATE6 Qc1xf4 Bd6xf4 Rh4xh5 g6xh5 Rh1xh5
>>> Bf4-h6 Rh5xh6 Qc7-h2 Kg2xh2 b5-b4 Rh6-h8
>>
>>Based on the performance of several progs, it's possible that this is a position
>>you should worry about. Most find the mate in 5 secs or less.
>>
>>Will
>
>I think that finding the mate fast is not very important.
>It is more important to find the move fast but it is also not the most important
>thing.
>
>public Movei is even slower than the baron in finding the move.
>Movei can find it relatively faster if I remove pruning based on evaluation but
>removing pruning based on evaluation is going to make it play weaker.
>
>Latest movei fail high on the move faster because I improved my condition of
>pruning based on evaluation but it still cannot find the mate fast and only find
>high score with no mate first.
>
>Uri
Latest Crafty looks like this:
starting thread 1
8 0.19 +1 1. Kf1!!
8 0.80 -1.51 1. Kf1 Rc8 2. Rg1 a5 3. Bg5 Nd5 4.
Kg2 Re8 5. Bxd5 cxd5
8-> 0.82 -1.51 1. Kf1 Rc8 2. Rg1 a5 3. Bg5 Nd5 4.
Kg2 Re8 5. Bxd5 cxd5
9 1.55 -1.22 1. Kf1 Ra8 2. Bc2 Rc8 3. Be4 Nd5 4.
Bxd5 cxd5 5. Qh6
9 1.83 +1 1. Qxf4!!
9 1.89 +3 1. Qxf4!!
9 2.02 +M 1. Qxf4!!
9 9.87 Mat06 1. Qxf4 Bxf4 2. Rxh5 gxh5 3. Rxh5 Bh6
4. Rxh6 Qh2+ 5. Kxh2 Kf8 6. Rh8#
9-> 9.88 Mat06 1. Qxf4 Bxf4 2. Rxh5 gxh5 3. Rxh5 Bh6
4. Rxh6 Qh2+ 5. Kxh2 Kf8 6. Rh8#
10 10.18 Mat06 1. Qxf4 Bxf4 2. Rxh5 gxh5 3. Rxh5 Bh6
4. Rxh6 Qh2+ 5. Kxh2 Kf8 6. Rh8#
10-> 10.20 Mat06 1. Qxf4 Bxf4 2. Rxh5 gxh5 3. Rxh5 Bh6
4. Rxh6 Qh2+ 5. Kxh2 Kf8 6. Rh8#
It sometimes does not find the mate at depth 9 due to late move reductions
interfering somewhere along the way. but it always finds the move Qxf4 very
quickly, and always has a score of +10 or better even when it fails to find the
mate, which is enough for me...
The above on my dual xeon 2.8ghz hardware...
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