Author: leonid
Date: 15:41:48 11/04/01
Go up one level in this thread
On November 04, 2001 at 17:39:18, Heiner Marxen wrote: >On November 04, 2001 at 10:45:12, leonid wrote: > >>On November 04, 2001 at 08:59:37, Paul wrote: >> >>>On November 04, 2001 at 07:54:58, leonid wrote: >>> >>>>Hello! >>> >>>Hi ... Pretz's first thoughts on a p3/1000 ... >>> >>>>This one is easy: >>>> >>>>[D]Q7/3qq3/2qQqk2/1nQRNqq1/nBKRRNq1/PrbBQq2/1PrPq3/2Bb4 w - - >>> >>>00:05 WM9 07 Qh8+ Qgg7 Nxd7+ Qcxd7 Nh5+ Qfxh5 Rxe6+ Qgxe6 Qef4+ Qxf4 Rxf4+ Qf5 >>>Rxf5+ Kg6 Qg1+ Qg5 Qxg5# > >Hi to both of you! > >5 seconds? Well, Chest is not _that_ fast, but this one is comparatively >easy: in 111.46 seconds (K7/600, 350 MB) Chest confirms that Qh8+ is the >only solution in 9 moves: > >PV: Qh8+ Qgg7 Nxd7+ Qcxd7 Nh5+ Qfxh5 Rxe6+ Qgxe6 Qef4+ Qxf4 Rxf4+ Qf5 Rxf5+ Kg6 >Qg1+ Qg4+ Rf4# > >Except for the last 2 plies identical to your line. Timing: > ># 1 0.00s 0kN 0.92 1- 0 ># 2 0.00s 0kN [ 48.00] 1.00 1- 0 ># 3 0.01s 0kN [ 8.92] 0.95 43- 0 ># 4 0.08s [ 8.00] 3kN [ 7.19] 1.17 327- 0 ># 5 0.42s [ 5.25] 21kN [ 6.79] 1.30 2391- 0 ># 6 1.81s [ 4.31] 88kN [ 4.20] 1.56 10849- 0 ># 7 7.28s [ 4.02] 357kN [ 4.07] 1.98 45853- 0 ># 8 28.55s [ 3.92] 1406kN [ 3.94] 2.46 180809- 0 ># 9 111.45s [ 3.90] 5597kN [ 3.98] 3.17 706062- 0 > >Yes, a very "mild" EBF. > > >>>>But if you want to solve something that is not difficult, almost the same but >>>>demand more thinking, then try this: >>>> >>>>[D]Q7/3qq3/2qNqk2/1nNRNqq1/nPKPRNq1/PrbBQq2/1PrQq3/2Bb4 w - - >>> >>>00:35 WM13 09 Qh8+ Qeg7 Nxd7+ Qexd7 Nh5+ Q5xh5 Rxf5+ Qfxf5 Qeh6+ Qhg6 Q6xg7+ >>>Qgxg7 Qdh6+ Qfg6 Rf4+ Qxf4 Qxg6+ Ke7 Qgxg7+ Qf7+ Qxf7+ Kxd6 Qf4+ Ke7 Qhf8# >>> >>>Not sure of course whether these are the shortest possible mates ... > >This one is significantly harder for Chest. After 4.2 hours (K7/600, 350 MB) >it confirms, again: Qh8+ is the only shortest solution in 13 moves: > >PV: Qh8+ Qeg7 Nxd7+ Qexd7 Nh5+ Q5xh5 Rxf5+ Qfxf5 Qeh6+ Qhg6 Q6xg7+ Qgxg7 Qdh6+ >Qfg6 Rf4+ Qxf4 Qxg6+ Ke7 Qgxg7+ Qf7+ Qxf7+ Kxd6 Bf4+ Qe5 Bxe5# > ># 1 0.00s 0kN 0.87 1- 0 ># 2 0.00s 0kN 1.00 1- 0 ># 3 0.01s 0kN [ 7.98] 0.94 44- 0 ># 4 0.06s [ 6.00] 3kN [ 7.39] 1.05 249- 0 ># 5 0.21s [ 3.50] 12kN [ 4.79] 1.27 1171- 0 ># 6 0.87s [ 4.14] 51kN [ 4.14] 1.64 4834- 0 ># 7 3.53s [ 4.06] 219kN [ 4.25] 2.15 20696- 0 ># 8 10.65s [ 3.02] 657kN [ 3.00] 2.95 61072- 0 ># 9 38.86s [ 3.65] 2677kN [ 4.07] 3.91 217967- 0 ># 10 171.46s [ 4.41] 11033kN [ 4.12] 4.87 1045649- 1 ># 11 554.99s [ 3.24] 30770kN [ 2.79] 5.67 3823600- 4947 ># 12 2482.73s [ 4.47] 112283kN [ 3.65] 5.53 18494015- 9748454 ># 13 14165.08s [ 5.71] 558147kN [ 4.97] 5.27 111698871- 102950970 > >It starts out even faster than for the first problem, and although the EBF >stays quite moderate, the additional 4 moves depth make a lot of difference. > >One statistics came as a surprise: for several depthes the EBF was not >from enumerating alternate white moves, but from enumerating more black >defense moves! I do not recall to have seen that before: > >depth w moves b moves w quot b quot >mvx 13: 22 28 [ 22.000 1.273] 21 >mvx 12: 167 327 [ 5.964 1.958] 109 >mvx 11: 1550 5746 [ 4.740 3.707] 318 4 >mvx 10: 6634 25390 [ 1.155 3.827] 1124 27 >mvx 9: 24984 94753 [ 0.984 3.793] 3569 173 >mvx 8: 89914 322532 [ 0.949 3.587] 14073 647 >mvx 7: 364201 1143166 [ 1.129 3.139] 44813 2043 >mvx 6: 1553495 3780853 [ 1.359 2.434] 171837 6558 >mvx 5: 6995183 13062507 [ 1.850 1.867] 821338 22892 >mvx 4: 32190163 47679286 [ 2.464 1.481] 2308374 86151 >mvx 3: 137230996 151136869 [ 2.878 1.101] >mvx 2: 128053285 32693591 [ 0.847 0.255] >mvx 1: 1690987 0 [ 0.052 ] > >Between depth 10 and 5 (depth to go) black contributed more than white to EBF. > > >Hmmm... isn't it already a long time that Pretz did not find a shortest >solution? Can that happen at all? Shouldn't we replace Chest with Pretz? >It is so much faster :-)) [ok, just kidding :-] Hi, Heiner! Liked very much your result. It look like that you was better that me on this. Nine moves deep position took for mine 10 min and 10 sec. And second was solved only 12 moves deep, when I looked into my result. 13 was taken by selective. 12 moves deep took already 8 hours and 32 min. Celeron 600Mhz. Cheers, Leonid. >Cheers, >Heiner > > >>>>Please indicate your result. >> >>Hi, Paul! >> >>Now you reached me for sure. On first and second position, your time is better >>that mine. First took 9 second for selective search 9 moves deep, and second 62 >>sec for selective in 13 moves. Both solutions are the shortest possible. I >>solved both by brute force. Branching factor is very mild for both of them. >> >>Cheers, >>Leonid.
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