Author: Tony Werten
Date: 13:50:02 06/15/04
Go up one level in this thread
On June 15, 2004 at 13:17:57, Vincent Diepeveen wrote: >On June 14, 2004 at 19:20:57, Anthony Cozzie wrote: > >It has nothing to do with double nullmove not finding it. Instead double >nullmove *does* find this. > >Only normal nullmove doesn't find it. > >It's of course like so many 'zugzwangs' another evaluation issue. > >Just be sure you evaluate qd2+ kxg4 qe3 b5 axb5 as more positive than some >positions which start with gxh5. I don't think it's an evaluation issue. The difference in score is over 10 pawns. I your program doesn't see that within 30 secs, it's either buggy or pruning like crazy or blindly nullmoving. Tony > >That's all. > >Diep finds it at 11 ply : > >00:00 22 22 0 (2) 1 (0,0) -0.471 g4xh5 Kg5xh5 >00:00 266 266 0 (2) 2 (0,1) -0.471 g4xh5 Kg5xh5 >00:00 835 835 0 (2) 3 (0,3) -0.061 g4xh5 Qh4-g4 Kg2-f1 g6xh5 Qd4xb6 Qg4xe4 Qb >6xa5 Kg5-h6 >00:00 147450 2949 0 (2) 4 (0,6) -0.061 g4xh5 Qh4-g4 Kg2-f1 g6xh5 Qd4xb6 Qg4xe4 Q >b6xa5 Kg5-h6 >00:00 147680 7384 0 (2) 5 (0,15) -0.061 g4xh5 Qh4-g4 Kg2-f1 g6xh5 Qd4xb6 Qg4xe4 >Qb6xa5 Kg5-h6 >00:00 180507 25271 0 (2) 6 (2,35) -0.133 g4xh5 Qh4-g4 Kg2-f1 Qg4-f4 Kf1-g1 g6xh5 > Qd4xb6 Qf4-e5 >00:00 192151 74939 0 (2) 7 (10,92) -0.139 g4xh5 Qh4-g4 Kg2-f1 Qg4-f4 Kf1-g1 Qf4- >g3 Kg1-h1 g6xh5 Qd4xb6 Qg3-e5 >00:01 229359 311929 0 (2) 8 (25,245) -0.080 g4xh5 Qh4-g4 Kg2-f2 Qg4-f4 Kf2-g1 Qf >4-g3 Kg1-h1 >00:02 248265 585907 0 (2) 9 (56,492) -0.547 g4xh5 Qh4-g4 Kg2-f2 Qg4-f4 Kf2-g1 g6 >xh5 Qd4xb6 Qf4xe4 Qb6xa5 Kg5-g4 Qa5-c5 Qe4-b1 Kg1-h2 Qb1xb3 >00:06 271934 1707751 0 (2) 10 (145,1157) -0.561 g4xh5 Qh4-g4 Kg2-f2 Qg4-f4 Kf2-g >1 g6xh5 Qd4xb6 Qf4xe4 Qb6xa5 Kg5-g4 Qa5-c5 Qe4-e1 Kg1-g2 Qe1-g3 Kg2-h1 Qg3-h3 Kh >1-g1 Qh3xb3 >00:18 283545 5205900 0 (2) 11 (368,2660) -0.836 g4xh5 Qh4-g4 Kg2-h2 Qg4xh5 Kh2-g >3 Qh5-g4 Kg3-f2 Qg4-e6 Qd4-e3 Kg5-f6 Qe3-d4 Kf6-f7 Qd4-e3 Kf7-g7 >++ d4-d2 procnr=0 terug=-561 org=[-836;-835] newwindow=[-836;520000] >00:34 293568 10013609 0 (2) 11 (565,3928) 11.263 Qd4-d2 Kg5xg4 Qd2-e3 b6-b5 a4xb >5 a5-a4 b5-b6 a4xb3 b6-b7 b3-b2 b7-b8Q Qh4-h1 Kg2xh1 b2-b1Q Kh1-g2 >00:39 297525 11814753 0 (2) 12 (592,4329) 11.263 Qd4-d2 Kg5xg4 Qd2-e3 b6-b5 a4xb >5 a5-a4 b5-b6 a4xb3 b6-b7 b3-b2 b7-b8Q Qh4-h1 Kg2xh1 b2-b1Q Kh1-g2 >01:39 304837 30212461 0 (2) 13 (1154,8778) 11.263 Qd4-d2 Kg5xg4 Qd2-e3 b6-b5 a4x >b5 a5-a4 b5-b6 a4xb3 b6-b7 b3-b2 b7-b8Q Qh4-h1 Kg2xh1 b2-b1Q Kh1-g2 >02:37 312094 49042542 0 (2) 14 (1324,10654) 11.263 Qd4-d2 Kg5xg4 Qd2-e3 b6-b5 a4 >xb5 a5-a4 b5-b6 a4xb3 b6-b7 b3-b2 b7-b8Q Qh4-h1 Kg2xh1 b2-b1Q Kh1-h2 Qb1-c2 Qe3- >f2 > >>On June 14, 2004 at 16:31:17, Jaime Benito de Valle Ruiz wrote: >> >>>[d]8/8/1p4p1/p5kp/Pp1QP1Pq/1P6/6K1/8 w - - 0 62 >>> >>>White moves and wins! >>>Can your engine find the right answer and give the proper "crushing" score >>>(around 9 pawns!) along with a proper PV? How long does it take? >>>Mine doesn't find anything after a long long time (over an hour), but with >>>null-move disabled, it takes only a few seconds to show the full PV. >>>(Some engines find the right answer, but with a small score, an absurd PV, and >>>they change their mind some plies later) >>> >>>In this position the black king is in a very delicate position: After a couple >>>of moves, if the black queen moves, white checkmates inmediately, so both kings >>>and queens must remain still while pawns play on their own. >>> >>>Any good suggestion to avoid this problem with null-move? >>> >>>Regards, >>> >>> Jaime >> >>Zappa doesn't get it either (gxh5 @ 15 ply after 1 minute). Zappa relies on >>double nullmove for zugzwang avoidance. This works find for positions with 1 >>zugzwang, but in this position black gets hit with about 10 of them :) >> >>anthony
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