Author: Omid David Tabibi
Date: 03:10:05 04/20/04
Go up one level in this thread
On April 19, 2004 at 22:50:56, Robert Hyatt wrote:
>On April 19, 2004 at 15:49:14, Andrew Williams wrote:
>
>>On April 18, 2004 at 19:56:25, Andrew Wagner wrote:
>>
>>Try searching longer. PM is getting this at ply 27 (78kns, 0.76 seconds) at the
>>moment, although I've seen it return the correct move at various different plies
>>over the years.
>>
>>Andrew
>
>Something might be wrong. It is a 26 ply combination to win a pawn, with no
>hash table at all... Hashing usually lets us hit the solution quicker. IE
>Crafty typically solves it at depth=18...
In his article "PEASANT: An endgame program for kings and pawns", Newborn
writes: "Position 70 would require a 30-ply search (25,000 hours)"
But running the position on Falcon:
Falcon 1.0.12.6 running on GenuineIntel 733MHz 256MB:
depth time nodes nps score variation
18/18 0.12 17k 149k 0.76 1.a1b2 a7a6 2.b2c3 a6b7 3.c3d3 b7c7
4.d3e3 c7d7 5.e3d2 d7c7 6.d2d3 c7b6
7.d3c2 b6b7 8.c2c3 b7c7 9.c3c4 c7d7
19/20 1.05 284k 270k 0.76 1.a1b2 a7a8 2.b2c3 a8b7 3.c3d3
19/20 1.05 284k 270k 0.86 1.a1b1++
19/20 1.06 284k 268k 1.92 1.a1b1++
19/20 2.58 744k 288k 2.36 1.a1b1 a7b7 2.b1c1 b7c7 3.c1d1 c7d7
4.d1c2 d7c8 5.c2d2 c8d7 6.d2c3 d7e7
7.c3c4 e7d7 8.c4b5 d7c7 9.b5a5 c7b7
10.a5b4
It takes a mere 1 second at depth 19!
>
>
>>
>>> Ok, I've been banging my head against this one all day. This is Fine #70:
>>>[d]8/k7/3p4/p2P1p2/P2P1P2/8/8/K7 w - -
>>>
>>> Below is Trueno's output for the position. Of course, the correct result is
>>>+1.8 (Trueno counts pawns as .9) with the best move of Kb1. It finds that but
>>>then changes its mind. I've been told that this position is generally infamous
>>>for catching hash bugs. Anyone have any suggestions how to attack this one? Null
>>>move is off, and I'm evaluating material only, using a single replace-always
>>>hash table. Any suggestions would be VERY much appreciated). Andrew
>>>
>>> -------------------------------
>>> 8 | . | . | . | . | . | . | . | . |
>>> |-------------------------------|
>>> 7 | k | . | . | . | . | . | . | . |
>>> |-------------------------------|
>>> 6 | . | . | . | p | . | . | . | . |
>>> |-------------------------------|
>>> 5 | p | . | . | P | . | p | . | . |
>>> |-------------------------------|
>>> 4 | P | . | . | P | . | P | . | . |
>>> |-------------------------------|
>>> 3 | . | . | . | . | . | . | . | . |
>>> |-------------------------------|
>>> 2 | . | . | . | . | . | . | . | . |
>>> |-------------------------------|
>>> 1 | K | . | . | . | . | . | . | . |
>>> -------------------------------
>>> A B C D E F G H
>>>
>>>Fifty: 0 En Passant: 0
>>>Castle: 0000
>>>Ply: 0 To move: True
>>>
>>>
>>>1. Score: .9; Time: 0; nodes: 4; PV: a1-b2
>>>2. Score: .9; Time: 0; nodes: 15; PV: a1-b2 a7-b6
>>>3. Score: .9; Time: 0; nodes: 48; PV: a1-b2 a7-b6 b2-c3
>>>4. Score: .9; Time: 0; nodes: 111; PV: a1-b2 a7-b6 b2-c3 b6-c7
>>>5. Score: .9; Time: 0; nodes: 231; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4
>>>6. Score: .9; Time: 0; nodes: 408; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>7. Score: .9; Time: 0; nodes: 671; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7 c4-d3
>>>8. Score: .9; Time: 0; nodes: 1003; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7
>>>9. Score: .9; Time: 0; nodes: 1443; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4
>>>10. Score: .9; Time: 0; nodes: 1968; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7
>>>11. Score: .9; Time: 0; nodes: 2735; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7 c4-d3
>>>12. Score: .9; Time: 0; nodes: 3522; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7
>>>13. Score: .9; Time: 0; nodes: 4416; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4
>>>14. Score: .9; Time: 1; nodes: 5410; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4 e7-d7
>>>15. Score: .9; Time: 1; nodes: 6584; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4 e7-d7 c4-d3
>>>16. Score: .9; Time: 1; nodes: 7885; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7
>>>17. Score: .9; Time: 1; nodes: 9273; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4
>>>18. Score: .9; Time: 1; nodes: 10845; PV: a1-b2 a7-b6 b2-c3 b6-c7 c3-c4 c7-d7
>>>c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4 e7-d7
>>>19. Score: .9; Time: 1; nodes: 16249; PV: a1-b2 a7-b6 b2-c3 b6-b7 c3-c4 b7-b6
>>>c4-d3 b6-c7 d3-c4 c7-d7 c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4 e7-d7 c4-d3
>>>20. Score: .9; Time: 1; nodes: 18816; PV: a1-b2 a7-b6 b2-c3 b6-b7 c3-c4 b7-b6
>>>c4-d3 b6-c7 d3-c4 c7-d7 c4-d3 d7-e7 d3-c4 e7-d7 c4-d3 d7-e7 d3-c4 e7-d7 c4-d3
>>>d7-e7
>>>21. Score: 1.8; Time: 2; nodes: 30305; PV: a1-b1 a7-b6 b1-c2 b6-b7 c2-d2 b7-c7
>>>d2-d3 c7-b6 d3-e3 b6-c7 e3-f3 c7-d7 f3-g3 d7-e7 g3-h4 e7-f6 h4-h5 f6-f7 h5-g5
>>>f7-e8 g5-f5
>>>22. Score: 1.8; Time: 2; nodes: 40127; PV: a1-b1 a7-b6 b1-c2 b6-b7 c2-d2 b7-c7
>>>d2-d3 c7-b6 d3-e3 b6-c7 e3-f3 c7-d7 f3-g3 d7-e7 g3-h4 e7-f6 h4-h5 f6-f7 h5-g5
>>>f7-e8 g5-f5 e8-e7
>>>23. Score: 1.8; Time: 2; nodes: 50869; PV: a1-b1 a7-b6 b1-c2 b6-b7 c2-d2 b7-c7
>>>d2-d3 c7-b6 d3-e3 b6-c7 e3-f3 c7-d7 f3-g3 d7-e7 g3-h4 e7-f6 h4-h5 f6-f7 h5-g5
>>>f7-e8 g5-f5 e8-e7 f5-e4
>>>24. Score: 1.8; Time: 3; nodes: 64039; PV: a1-a2 a7-b6 a2-b3 b6-c7 b3-c3 c7-b6
>>>c3-c2 b6-a6 c2-d2 a6-b6 d2-e3 b6-c7 e3-f3 c7-d7 f3-g3 d7-e7 g3-h4 e7-f6 h4-h5
>>>f6-f7 h5-g5 f7-e8 g5-f5 e8-e7
>>>25. Score: 1.8; Time: 3; nodes: 75500; PV: a1-b2 a7-b6 b2-c3 b6-b7 c3-d2 b7-c7
>>>d2-d3 c7-b6 d3-e3 b6-c7 e3-f3 c7-d7 f3-g3 d7-e7 g3-h4 e7-f6 h4-h5 f6-f7 h5-g5
>>>f7-e8 g5-f5 e8-e7 f5-e4 e7-d7 e4-f5
>>>26. Score: 1.8; Time: 4; nodes: 83644; PV: a1-b2 a7-b6 b2-c3 b6-b7 c3-d2 b7-c7
>>>d2-d3 c7-b6 d3-e3 b6-c7 e3-f3 c7-d7 f3-g3 d7-e7 g3-h4 e7-f6 h4-h5 f6-f7 h5-g5
>>>f7-e8 g5-f5 e8-e7 f5-e4 e7-d7 e4-f5 d7-e7
>>>I play a1-b2
>>>Nodes: 83k; NPS: 21414; QNodes: 0; MO%: 98; FHA: 2; HC%: 55; Hash%: 58; NM%: 0;
>>>egtb hits: 0; Ext's: 0; Total time searched: 3.906
>>>
>>>(MO% = first-move fail-high percent; FHA isn't important; HC is the percent of
>>>time the hash move causes a cutoff; Hash% is the percent of time I find the move
>>>in the hash table; the rest is un-important)
>>>
>>>(told you it was a long post)
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