Author: Heiner Marxen
Date: 15:39:43 07/14/01
Go up one level in this thread
On July 14, 2001 at 17:12:20, leonid wrote: >On July 14, 2001 at 13:57:52, Heiner Marxen wrote: > >>On July 14, 2001 at 09:38:20, leonid wrote: >> >>>Hi! >>> >>>If you like to solve a mate then you have one position. >>> >>>[D]qr1b1rq1/P1P1P1P1/1q1k1q2/Q1RbR1Q1/1N1q1N2/1QnQnQ2/q1pKp1q1/3B4 w - - >>> >>>Please indicate your result. >>> >>>Thanks, >>>Leonid. >> >>According to Chest, there is no mate in 9 (4 min on K7/600, 350 MB hash). >>With an effective branching factor around 5 I will go one move deeper, >>which will take 4 hours or more... > >You have obviously better branching factor that me on this position. Even >without hash my should do better. Between 7 and 8 move (brute force) my >branching factor was 8.8. For this position it tend to deminish with depth. >Probably it is related with promotion of pawns. Will try to see it more closely >on other positions. > >This positions is for sure mate in 10, since you verified mate in 9. Yes, you are right. Here are the two PVs of Chest: PV: cxd8=Q+ Rfxd8 Qxf6+ Kd7 exd8=Q+ Qgxd8 Re7+ Qxe7 Rc7+ Qxc7 Qxe7+ Kxe7 Qxc7+ Ke8 Qh5+ Qg6 Qh8+ Bg8 Qhxg8# PV: cxd8=R+ Rfxd8 Qxf6+ Kd7 exd8=Q+ Qgxd8 Re7+ Qxe7 Rc7+ Qxc7 Qxe7+ Kxe7 Qxc7+ Ke8 Qh5+ Qg6 Qh8+ Bg8 Qhxg8# Only the first ply is different. Regarding the branching factor: depth time EBF[T] EBF[N] # 1 0.00s 0kN 0.96 1- 0 # 2 0.00s 0kN [ 35.00] 1.00 1- 0 # 3 0.03s 2kN [ 13.82] 0.97 91- 0 # 4 0.24s [ 8.00] 19kN [ 9.62] 1.23 317- 0 # 5 1.91s [ 7.96] 149kN [ 8.00] 1.51 2597- 0 # 6 13.29s [ 6.96] 1020kN [ 6.85] 1.87 22269- 0 # 7 91.70s [ 6.90] 7068kN [ 6.93] 2.33 189995- 0 # 8 506.46s [ 5.52] 38151kN [ 5.40] 3.02 1347180- 1 # 9 2670.72s [ 5.27] 192810kN [ 5.05] 3.87 8654541- 885112 # 10 22818.97s [ 8.54] 1461617kN [ 7.58] 5.00 94537421- 85789520 >Mine solved it by selective in 10. In dispite of very easy and simple >parameters, mine found mate only after 10 min and 55 sec search. I for sure must >work on my program but for now I wait for 64 bits Intel. It is almost with us! >Once I will have the money and it will be more accessible, new and exciting >programming could start! I do expect that many people here will come with many >interesting development because of this new chip. I don't share your optimism. Not many do assembly, any more. Well, we'll see :-) Cheers, Heiner
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