Author: Robert Hyatt
Date: 12:52:54 03/07/06
Go up one level in this thread
On March 07, 2006 at 04:49:35, Uri Blass wrote:
>On March 07, 2006 at 03:27:45, Richard Pijl wrote:
>
>>On March 06, 2006 at 22:49:11, Dann Corbit wrote:
>>
>>>Unstoppable passed pawn. What does your program see as far as pawn score here?
>>>[D] 8/7p/5k2/5p2/p1p2P2/Pr1pPK2/1P1R3P/8 b - - bm Rxb2
>>
>>You'll need to know that two connected passers beat a rook when progressed to
>>3rd rank (or one to 4 and 2) and the defending king is too far away.
>>You will not find it in reasonable time without this 'knowledge' in your passed
>>pawn evaluation if you are doing any kind of pruning (including nullmove
>>pruning)
>
>This is not correct
>
>Movei find it in a few seconds without that knowledge and it certainly has
>pruning including null move pruning.
>
>Here is the analysis at depth 12
>
>12 106 265 1659869 b3b8 h2h4 h7h5 d2g2 b8b3 g2f2 b3b7 f2d2 f6e6 d2g2 e6d5
>12 107 314 1976669 b3b7
>12 111 360 2286743 b3b7 h2h4 h7h5 d2g2 b7b8 g2f2 b8g8 e3e4 f5e4 f3e4 g8e8 e4f3
> f6f5 f2g2
>12 112 429 2811982 b3b2
>12 141 454 3042096 b3b2
>12 240 543 3690983 b3b2 d2b2 c4c3 b2b6 f6g7 b6b7 g7h6 b7b6 h6h5 b6b5 c3c2 b5f5
> h5h4 f5f6 h7h5 f6c6 d3d2 c6c2 d2d1q c2e2
>12 240 554 3778228 b3b2 d2b2 c4c3 b2b6 f6g7 b6b7 g7h6 b7b6 h6h5 b6b5 c3c2 b5f5
> h5h4 f5f6 h7h5 f6c6 d3d2 c6c2 d2d1q c2e2
>
>>It took me a little while to get this correct in the Baron, but now it solves it
>>at a 3 ply search in 0.02 seconds on a Xeon 2.8 Ghz:
>>
>> ply time nodes score pv
>> 2( 2)& 0:00.02 115 +0.78 Kf6-e6 e3-e4
>> 2( 2)& 0:00.02 174 +0.90 Rb3-b5 Rd2-g2
>> 2( 2)& 0:00.02 223 +0.93 Rb3-b6 e3-e4 (f5xe4)
>> 2( 2)& 0:00.02 272 +1.01 Rb3-b7 e3-e4 (f5xe4)
>> 2( 2)& 0:00.02 321 +1.04 Rb3-b8 e3-e4 (f5xe4)
>> 2( 2). 0:00.02 393 +1.04 Rb3-b8 e3-e4 (f5xe4)
>> 3( 6)& 0:00.02 557 +1.20 Rb3-b8 e3-e4 f5xe4 Kf3xe4 Rb8-d8
>> 3( 6)+ 0:00.02 898 +1.99 Rb3xb2 (Rd2xb2) (c4-c3)
>> 3( 6)& 0:00.02 967 +3.16 Rb3xb2 Rd2xb2 c4-c3 Rb2-b6 Kf6-e7
>> 3( 6). 0:00.02 989 +3.16 Rb3xb2 Rd2xb2 c4-c3 Rb2-b6 Kf6-e7
>
>This knowledge is not correct and based on this knowledge it may find Rxb2 also
>in the following diagram with the same PV.
>
>
>[D]8/7p/5k2/5p2/p1p2P2/Pr1p1K2/1P1R3P/8 b - -
>
>Uri
I prefer to find this one tactically... here is crafty on my dual xeon:
12 0.29 -1 1. ... c3!!
12 0.32 -2.10 1. ... c3 2. bxc3 Rxc3 3. e4 fxe4+
4. Kxe4 Rxa3 5. h4 Rb3 6. Rxd3 Rxd3
7. Kxd3 a3 (s=10)
12-> 0.59 -2.10 1. ... c3 2. bxc3 Rxc3 3. e4 fxe4+
4. Kxe4 Rxa3 5. h4 Rb3 6. Rxd3 Rxd3
7. Kxd3 a3 (s=13)
13 0.71 -1 1. ... c3!!
13 0.78 -2.41 1. ... c3 2. bxc3 Rxc3 3. Rb2 Rxa3
4. Rb6+ Ke7 5. Rb7+ Kd6 6. Rb4 Kc5
7. Rd4 h6 <HT> (s=12)
13-> 1.30 -2.41 1. ... c3 2. bxc3 Rxc3 3. Rb2 Rxa3
4. Rb6+ Ke7 5. Rb7+ Kd6 6. Rb4 Kc5
7. Rd4 h6 <HT> (s=10)
14 1.63 +1 1. ... c3
14 1.91 -2.02 1. ... c3 2. bxc3 Rxc3 3. Ra2 Ke6 4.
h3 Kd5 5. Ra1 h5 6. Rb1 Rxa3 7. Rb5+
Kc4 8. Rxf5 d2 <HT> (s=9)
14 2.89 -1 1. ... Rxb2!!
14 7.17 -3.46 1. ... Rxb2 2. Rxb2 c3 3. Rb6+ Ke7
4. Rb7+ Kd6 5. Rb6+ Kc7 6. Rb1 c2 7.
Rc1 Kd6 8. e4 d2 9. e5+ Ke6 10. Rxc2
d1=Q+ (s=5)
14-> 7.76 -3.46 1. ... Rxb2 2. Rxb2 c3 3. Rb6+ Ke7
4. Rb7+ Kd6 5. Rb6+ Kc7 6. Rb1 c2 7.
Rc1 Kd6 8. e4 d2 9. e5+ Ke6 10. Rxc2
d1=Q+
15 8.03 -1 1. ... Rxb2!!
15 8.32 -3.99 1. ... Rxb2 2. Rxb2 c3 3. Rb6+ Ke7
4. Rb7+ Kd6 5. Rb6+ Kc7 6. Rb1 c2 7.
Rc1 Kb6 8. Kg3 d2 9. Rxc2 d1=Q 10.
Rc8
15-> 10.51 -3.99 1. ... Rxb2 2. Rxb2 c3 3. Rb6+ Ke7
4. Rb7+ Kd6 5. Rb6+ Kc7 6. Rb1 c2 7.
Rc1 Kb6 8. Kg3 d2 9. Rxc2 d1=Q 10.
Rc8 (s=9)
16 11.17 -4.13 1. ... Rxb2 2. Rxb2 c3 3. Rb6+ Ke7
4. Rb7+ Kd6 5. Rb6+ Kc7 6. Rb1 c2 7.
Rc1 Kb6 8. Kg3 d2 9. Rxc2 d1=Q 10.
Rb2+ Qb3 11. Rxb3+ axb3 (s=8)
16-> 17.22 -4.13 1. ... Rxb2 2. Rxb2 c3 3. Rb6+ Ke7
4. Rb7+ Kd6 5. Rb6+ Kc7 6. Rb1 c2 7.
Rc1 Kb6 8. Kg3 d2 9. Rxc2 d1=Q 10.
Rb2+ Qb3 11. Rxb3+ axb3 (s=9)
17 19.21 -4.44 1. ... Rxb2 2. Rxb2 c3 3. Rb6+ Ke7
4. Rc6 c2 5. Kf2 Kd7 6. Rc4 d2 7. Rxc2
d1=Q 8. Rc5 Qh5 9. Ke1 Qh4+ 10. Kd1
Ke6 <HT> (s=8)
2 seconds is good enough for me on this hardware, and I don't have to deal with
your other case, which produces this:
12 0.13 -2.53 1. ... c3 2. bxc3 Rxc3 3. Ke3 Rxa3
4. Kd4 h6 5. Kc4 Kg6 6. Kb4 Rb3+ 7.
Kxa4 Rc3 (s=6)
12-> 0.37 -2.53 1. ... c3 2. bxc3 Rxc3 3. Ke3 Rxa3
4. Kd4 h6 5. Kc4 Kg6 6. Kb4 Rb3+ 7.
Kxa4 Rc3 (s=11)
13 0.43 -2.52 1. ... c3 2. bxc3 Rxc3 3. Ke3 Rxa3
4. Kd4 Rb3 5. Kc4 Kg6 6. Rg2+ Kh5 7.
Ra2 Kg4 8. Rxa4 (s=10)
13 0.72 -1 1. ... Ke6!!
13 0.97 -3.06 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. Kf3
Kd4 5. Kf2 c3 6. bxc3+ Rxc3 7. Kg3
Rxa3 8. Kf3 (s=8)
13-> 1.19 -3.06 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. Kf3
Kd4 5. Kf2 c3 6. bxc3+ Rxc3 7. Kg3
Rxa3 8. Kf3
14 1.62 -3.14 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. Kf3
Kd4 5. h4 h5 6. Kf2 c3 7. bxc3+ Rxc3
8. Kg3 Rxa3
14-> 2.04 -3.14 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. Kf3
Kd4 5. h4 h5 6. Kf2 c3 7. bxc3+ Rxc3
8. Kg3 Rxa3
15 2.29 -3.14 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. h4
h5 5. Kf3 Kd4 <HT>
15-> 3.52 -3.14 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. h4
h5 5. Kf3 Kd4 <HT> (s=5)
16 4.23 -1 1. ... Ke6!!
16 5.07 -3.80 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. h4
h5 5. Kf3 Kd4 6. Kf2 c3 7. bxc3+ Rxc3
8. Kg1 Ke3 9. Ra2 Kxf4 (s=4)
16-> 6.85 -3.80 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. h4
h5 5. Kf3 Kd4 6. Kf2 c3 7. bxc3+ Rxc3
8. Kg1 Ke3 9. Ra2 Kxf4 (s=3)
17 8.97 -3.97 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. h4
h5 5. Kf3 Kd4 6. Kf2 c3 7. bxc3+ Rxc3
8. Kg3 Rxa3 9. Kf3 Kc3 10. Ke3 (s=2)
17-> 12.20 -3.97 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. h4
h5 5. Kf3 Kd4 6. Kf2 c3 7. bxc3+ Rxc3
8. Kg3 Rxa3 9. Kf3 Kc3 10. Ke3 (s=2)
18 15.09 -1 1. ... Ke6!!
18 16.23 -4.36 1. ... Ke6 2. h3 Kd5 3. Ke3 h6 4. h4
h5 5. Kf3 Kd4 6. Kf2 c3 7. bxc3+ Rxc3
8. Rd1 Rxa3 9. Rd2 Rb3 <HT>
time=23.33 mat=-1 n=51170490 fh=92% nps=2.19M
ext-> chk=2184947 1rep=33497 mate=2652
predicted=0 nodes=51170490 evals=25499524 50move=0
endgame tablebase-> probes=6 hits=6
SMP-> split=1893 stop=165 data=8/64 elap=23.33
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