Author: leonid
Date: 16:39:32 09/14/02
Go up one level in this thread
On September 14, 2002 at 16:58:23, Heiner Marxen wrote: >On September 14, 2002 at 10:44:49, leonid wrote: > >>On September 14, 2002 at 10:14:52, Paul wrote: >> >>>On September 14, 2002 at 09:47:21, leonid wrote: >>> >>>>On September 14, 2002 at 09:26:25, leonid wrote: >>>> >>>>>On September 14, 2002 at 08:51:31, Paul wrote: >>>>> >>>>>>On September 14, 2002 at 07:55:35, leonid wrote: >>>>>> >>>>>>>Hi, >>>>>>> >>>>>>>This mate is easy and only 9 moves deep: >>>>>>> >>>>>>>[D]bqRNNkqr/Q7/qPnPqBqN/Q4q2/5Qr1/5q2/5nQ1/bQqQqBKR w - - >>>>>> >>>>>>Hi Leonid, >>>>>> >>>>>>Pretz (p3/1000) also finds this one easy, it gets this in 3 seconds: >>>>>> >>>>>>00:03 WM9 06 Nxe6+ Qgxe6 Be7+ Nxe7 dxe7+ Qxe7 Qaxf5+ Bf6 Nxf6+ Qaxc8 Nh7+ Ke8 >>>>>>Qxg6+ Rxg6 Qgxg6+ Qf7 Qaxf7# > >Chest (Athlon 1500+, 128MB hash) confirms this in 56.21 secs: Hi, Heiner! >PV: Nxe6+ Qgxe6 Bg7+ Bxg7 Qbxf5+ Bf6 Nxf6+ Qaxc8 Nh7+ Ke8 d7+ Kd8 dxc8=Q+ Kxc8 >Qfc7+ Qxc7 Qxc7# > > Nxe6+ Qgxe6 Bg7+ Bxg7 Qbxf5+ ...+6 > Qxg7 Qbxf5+ ...+3 > Qexe6 Be7+ =*= dxe7+ ...+5 > Qfxe6 Bg7# Probably our branching were close even if my initial speed (before 4 moves) should be better for You. I looked brute force only 8 moves in order to know that it is really 9 moves position. It, on my usual setting (Celeron 600Mhz, no hash) was: Move Time Branching factor NPS 4 0.27 sec 125k 4.6 5 1.26 sec 105k 5.34 6 6.75 sec 80k 4.95 7 33.46 79k 5.08 8 2 min 50 sec >It is so easy/fast, because black has mating resources, too, like Rxg2#. > >>>>>>>Still, maybe, You will be tempted for something more heavy and I this way will >>>>>>>be able to find more on this position: >>>>>>> >>>>>>>[D]2qRQq2/p6P/q1BqqR1N/r6B/n1QNQQ1B/r6k/b1QKNP1q/bq4qn w - - >>>>>>> >>>>>>>On description of this mate I can see that it was solved by selective in 13 >>>>>>>moves but brute force search went not up to the end in order to find shortest >>>>>>>move. Brute force search, without finding any mate, went only 9 moves deep. >>>>>> >>>>>>This one was indeed a lot more difficult, mine didn't fare so well here: >>>>>> >>>>>>06:49 WM11 07 Q8xe6+ Qdxe6 Qff3+ Rxf3 Qxf3+ Kxh4 Nhf5+ Rxf5 Nxf5+ ... >>>>>> >>>>>>So it found a mate in 11 in almost 7 minutes, with an incomplete pv ... these >>>>>>d#*&#@rned hashtables ;) ... will have to think about this ... any tips anyone? >>>>>> >>>>>>>Please indicate Your result. >>>>>>> >>>>>>>Thanks, >>>>>>>Leonid. >>>>>> >>>>>>Thanks for your mates as usual ... >>>>> >>>>>Thanks, Paul! >>>>> >>>>>Now I can see that second one is no far then 11 moves. I can even put this >>>>>position at 10 moves by brute force for night. If braching factor will not >>>>>suddenly jump, then it should be enough time for me for finding its depth. >>>>> >>>>>First position have excellent time! >>>>> >>>>>Mine, on usual setting, found mate in 1.75 sec. >>>>> >>>>>Cheers, >>>>>Leonid. >>>> >>>>Paul, just after writing my message, I started to see second position in my file >>>>to indicate 11 moves. When I finally found it (I not indicate before on what >>>>page I had it), I looked that it was in reality solved by selected in 11 moves, >>>>just as You said. Before upper part of page was covered with page keeper and it >>>>is how I missed some additional description. If I knew this yesterday, when I >>>>found this position, I could put search for 10 moves by brute force at night. >>> >>>Hey!! ... so you tricked us ... that's not fair ... I would have found it much >>>faster if I'd known! ... just kiddin' ... :) >> >>I was actually tricked by myself. I did expected that this position was very >>difficult since I could see that it was solved by very slow selective and only >>at 13 moves. 13 moves at large default setting (I use it before searching by >>much easier solution) took 13.5 minutes to solve. When I looked into 11 moves >>selective solution its paramether indicated that solution was almost simple. >> >> >>>>Selective in 11 moves was solved in 18 seconds. Usual setting. >>> >>>Not bad at all ... you really should implement hash to get a bit faster though >>>... ;) > >Chest is still running for depth 11, but after 3478 secs has already reported >that there is no mate in 10. So, we are already sure, that 11 is minimal >depth. Paul just said to me that there are no mate in 10. ># 4 0.09s 17kN [ 10.28] 1.07 737- 0 ># 5 0.96s [ 10.67] 137kN [ 7.88] 1.21 8654- 0 ># 6 6.32s [ 6.58] 791kN [ 5.79] 1.49 66512- 0 ># 7 31.30s [ 4.95] 3675kN [ 4.65] 2.11 351756- 0 ># 8 143.98s [ 4.60] 16349kN [ 4.45] 2.73 1718242- 7352 ># 9 668.36s [ 4.64] 73337kN [ 4.49] 3.46 8452143- 5252957 ># 10 3477.74s [ 5.20] 373030kN [ 5.09] 4.02 45004182- 41804949 On mine, with usual setting: Move Time Branching factor NPS 4 1.26 sec 113k 8.0 5 10.16 sec 67k 7.52 6 1 min 16 sec 67k 6.28 7 7 min 58 57k 5.21 8 41 min 35 sec 59k 5.21 9 3h 37m 14s 60k Cheers, Leonid. >Cheers, >Heiner > > >>I do expect that one day I will come back to my programming. At least, this last >>week I had plaintly of work and it could be that needed second computer will be >>not that long to wait for. Still 64 bits gadget will be ideal to start with. I >>am sure that when new, 64 bits, computer will arrive chatting of people here >>will be very animated. Too many things to redo, or write from scratch. >> >>Cheers, >>Leonid. >> >>>>Cheers, >>>>Leonid. >>> >>>Groetjes, >>>Paul
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