Author: Paul
Date: 12:43:57 10/03/01
Go up one level in this thread
On October 03, 2001 at 11:53:39, Heiner Marxen wrote: >On October 02, 2001 at 09:52:50, Paul wrote: > >>On October 02, 2001 at 08:41:20, leonid wrote: >> >>>[D]kq4BK/pq4QQ/2qq1P2/1NnqBnN1/3PpP2/2P2r2/RQ4qr/RQ4bb w - - >>> >>>I have said that this position is for "Champions" only having in mind that some >>>people will try to solve it by brute force. Brute force is the only way to know >>>minimal nomber of moves that lead to mate. But it could be not all the time >>>easy. When I tried this position on two professional program, I was impressed. >>>On Celeron 600Mhz, and with 1M of hash, one expected to solve position in around >>>4000 years. Other, with no hash, after around 11000000000 years of thinking >>>expected to recognize shortest mate. >>> >>>Please indicate your result. >>> >>>Thanks, >>>Leonid. >> >>Hi Leonid, >> >>I just now started to look at both your positions, the simple one from yesterday >>and this one, and I think you have a bit of a twisted nomenclature! >> >>This one is the simple one, the other one is more difficult. Even if this one >>seems to be a mate in 12, and the other in 9. But maybe that's only the case for >>Pretz, I'm curious about LLchess. >> >>For this one I find a mate in 12 in 3 seconds by applying some gentle force: >> >>00:03 WM12 12 Rxa7+ Q8xa7 Rxa7+ Kb8 Rxb7+ Nxb7 Qf8+ Qc8 Qxc8+ Kxc8 Nxd6+ Nfxd6 >>Be6+ Kd8 Qb6+ Ke8 Bd7+ Kf8 Bxd6+ Nxd6 Qb8+ Nc8 Qxc8# > >Hi Leonid, Hi Paul! > >Since 1BELCT has finished, and my PC is reassembled, its time for a mate... :-) Heiner, read you had a crash, sorry 'bout that ... but, I'd be happy to send you all of Leonid's previous problems, so you can run them again ... ;0 >Chest confirms the above: Rxa7+ is the only key move for the shortest >solution. It gives nearly the same PV: > >PV: Rxa7+ Q8xa7 Rxa7+ Kb8 Rxb7+ Nxb7 Qf8+ Qc8 Qxc8+ Kxc8 Nxd6+ Nfxd6 Be6+ Kd8 >Qb6+ Ke8 Bd7+ Kf8 Bxd6+ Qxd6 Qxd6+ Nxd6 Ne6# > >(9.5 minutes on a K7/600 with 350 MB hash). > >Heiner Just for comparison: with the command 'chest319 -Z12 -b x.epd' in a DOS box under Windows XP it took about 5'45" on my p3/1000. That's a linear speedup, although I used probably only ~40MB hash (that's default, don't know how to set hash in Chest, any tips?). Paul
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.