Author: Robert Hyatt
Date: 11:09:33 11/22/00
Go up one level in this thread
On November 22, 2000 at 11:55:03, Oliver Roese wrote: >On November 22, 2000 at 10:17:21, Robert Hyatt wrote: > >>On November 22, 2000 at 00:41:00, Oliver Roese wrote: >> >>>On November 21, 2000 at 14:56:47, Robert Hyatt wrote: >>> >>>>On November 21, 2000 at 14:45:13, Oliver Roese wrote: >>>> >>>>>On November 21, 2000 at 03:25:00, Dann Corbit wrote: >>>>> >>>>>>[D]8/8/2Kp4/3P1B2/2P2k2/5p2/8/8 w - - bm Bc8; id "WAC.146"; >>>>>> >>>>>>Searched Move: b6+ >>>>>>Right = 1/2 Stime = 10.9 Total NPS = 429381 <time_sq> = 120 <depth> = 20 >>>>>> >>>>>>White to Move Book Move(s): Bc8 >>>>>> Test Position: "WAC.146" >>>>>> 1. 2.46 0 78031 1. Bh3 >>>>>> 1. 2.52 0 78036 1. Be6 >>>>>> 1. 2.54 0 78037 1. Bd7 >>>>>> 1. 2.54 0 78051 1. Bd7 >>>>>> 2. 2.53 0 78062 1. Bd7 Ke5 >>>>>> 2. ++ 0 78134 1. Bh7 >>>>>> 2. 1.82 0 78343 1. Bd7 f2 >>>>>> 2. 2.51 0 78365 1. Be6 Ke5 >>>>>> 2. 2.52 0 78424 1. Bd3 Ke3 >>>>>> 2. 2.52 0 78496 1. Bd3 Ke3 >>>>>> 3. 2.55 0 78525 1. Bd3 Ke3 2. Bf5 >>>>>> 3. ++ 0 78826 1. Bh7 >>>>>> 3. 2.55 0 79404 1. Bd3 Ke3 2. Bf5 >>>>>> 3. 2.55 0 80628 1. Bd3 Ke3 2. Bf5 >>>>>> 4. 2.64 0 80953 1. Bd3 Ke3 2. c5 dxc5 >>>>>> 4. 2.64 0 83123 1. Bd3 Ke3 2. c5 dxc5 >>>>>> 5. 2.54 0 84780 1. Bd3 Ke3 2. Bf5 Kf4 3. Bd7 >>>>>> 5. ++ 0 91118 1. Bc8 >>>>>> 5. -- >>>>>> 5. 2.54 0 94138 1. Bd3 Ke3 2. Bf5 Kf4 3. Bd7 >>>>>> 5. 5.87 0 99653 1. Bc8 f2 2. Bh3 Kg3 3. Bf1 >>>>>> 5. 5.87 0 116910 1. Bc8 f2 2. Bh3 Kg3 3. Bf1 >>>>>> 6. -- >>>>>> 6. ++ 0 117724 1. Bc8 >>>>>> 6. 5.87 0 118439 1. Bc8 f2 2. Bh3 Kg3 3. Bf1 Kf4 >>>>>> 6. 5.87 0 161237 1. Bc8 f2 2. Bh3 Kg3 3. Bf1 Kf4 >>>>>> 7. 5.87 0 165796 1. Bc8 f2 2. Bh3 Ke3 3. Bf1 Kd4 >>>>>> 7. ++ 0 186436 1. Bh3 >>>>>> 7. -- >>>>>> 7. 5.87 0 191756 1. Bc8 f2 2. Bh3 Kg3 3. Bf1 Kf4 4. Kxd6 >>>>>> 7. 6.64 0 212491 1. Bh3 Kg3 2. Bf1 Kf2 3. Kxd6 Ke1 4. Bh3 >>>>>> 7. 6.64 0 212520 1. Bh3 Kg3 2. Bf1 Kf2 3. Kxd6 Ke1 4. Bh3 >>>>>> 8. -- >>>>>> 8. ++ 0 221385 1. Bh3 >>>>>> 8. 6.45 0 223648 1. Bh3 Kg3 2. Bf1 Kf2 3. Kxd6 Ke1 4. Bh3 f2 >>>>>> 8. 6.45 0 223732 1. Bh3 Kg3 2. Bf1 Kf2 3. Kxd6 Ke1 4. Bh3 f2 >>>>>> 9. 6.45 0 232656 1. Bh3 Kg3 2. Bf1 Kf2 3. Kxd6 Ke1 4. Bh3 f2 5. c5 >>>>>> 9. ++ 0 264037 1. Bd3 >>>>>> 9. 8.88 0 295723 1. Bd3 Ke3 2. c5 dxc5 3. d6 Kd2 4. d7 c4 5. d8=Q >>>>>> 9. 8.88 0 304900 1. Bd3 Ke3 2. c5 dxc5 3. d6 Kd2 4. d7 c4 5. d8=Q >>>>>> 10. ++ 0 314109 1. Bd3 >>>>>> 10. 14.23 1 495219 1. Bd3 Ke3 2. c5 Kd4 3. cxd6 Kc3 4. d7 Kd2 5. d8=Q >>>>>>Ke3 >>>>>> 10. 14.23 1 525349 1. Bd3 Ke3 2. c5 Kd4 3. cxd6 Kc3 4. d7 Kd2 5. d8=Q >>>>>>Ke3 >>>>>> 11. ++ 1 529553 1. Bd3 >>>>>> 11. 16.49 6 1363057 1. Bd3 Kg3 2. c5 Kf4 3. cxd6 Ke5 4. d7 Kf4 5. d8=Q >>>>>>Ke3 >>>>>> 11. 16.49 6 1393518 1. Bd3 Kg3 2. c5 Kf4 3. cxd6 Ke5 4. d7 Kf4 5. d8=Q >>>>>>Ke3 >>>>>> 12. ++ 6 1402113 1. Bd3 >>>>>> 12. MATE+ 33 9555958 1. Bd3 f2 2. c5 Ke3 3. cxd6 Kxd3 >>>>>> 12. MATE+ 33 9738198 1. Bd3 f2 2. c5 Ke3 3. cxd6 Kxd3 >>>>>> >>>>>>node_count = 9738198 quiescent nodes = 10482 eval_count = 4534996 >>>>>>hash hits = 2251420 hash moves = 342378 pawn hash hits = 4522278 >>>>>>node_rate = 290779 null cuts = 935545 exten = 747422 int_iter = 120 >>>>>>egtb_probes = 267932 egtb_hits = 267932 fail_high(%) = 93 >>>>> >>>>>After 1.Bd3 black can force a repetition of the position with >>>>>1...Ke3 2.Bf1 Kf2 3.Bh3 Kg3 4.Bf5 Kf4 (all forced) and white should soon come up >>>>>with a better idea... >>>>> >>>>>Oliver >>>> >>>>When I play the above move, I get a mate score from crafty. ie: >>>> >>>>after Bd3, ... >>>> (4) 17-> 51.30 -Mat40 1. ... Ke3 2. Bf1 Kf2 3. c5 Kxf1 4. >>>> cxd6 <HT> >>>> >>>>(which comes from tablebases of course...) >>>> >>>>Kf2 then leads to a mate in 39... >>>> >>>>3. Bh3 is not the move for white however... that leads to a repetition. white >>>>plays c5 to stay on the track to mating... Bh3 will also mate, but only after >>>>going through the 2-fold repetition first, and wasting time... >>> >>>I apologize if i was wrong here, but i just cant get it. >>>I saw 3.c5, but after 3...Kxf1 4.cxd6 f2 5.d7 K(e2) 6.d8=Q f1=Q a queen-ending >>>with a pawn up for white follows. Could you (or Bruce Morland) give some further >>>moves of the best line? Is it a forced queen swap or what?? >>>If white simply waits for ...f2 with 1.Bc8 black will never get a queen. >>>It is really hard to believe... >>> >>>Oliver >> >> >>after the 3. ... Kxf1 cxd6 is a mate in 38.. >> >>Here is the complete variation after 4 moves: >>5. d7! f2! 6. d8=Q! f1=Q! 7. Qb6! Qh1! 8. Qd4! Qf3 9. Qc5! Kd1 10. >>Kb6! Qf6+! 11. d6! Qd8+! 12. Qc7! Qf6! 13. Qc6! Qb2+! 14. Qb5! Qd4+! >>15. Qc5 Qf6! 16. Kc7! Qf4! 17. Qd5+! Ke1! 18. Kc8 Qc1+ 19. Kd8! Qe3 >>20. d7! Kf1! 21. Qc4+! Kg1 22. Kc8! Qh3! 23. Kc7! Qh2+ 24. Kb7 Qg2+! >>25. Qc6! Qg7! 26. Qc7 Qg2+! 27. Kb8! Qb2+! 28. Kc8! Qg2 29. Qa7+ >>Kf1! 30. Qa1+! Ke2 31. Qb2+ Kf1 32. Qxg2+! Kxg2! 33. d8=Q! Kf2 34. >>Qd3 Ke1 35. Qc2 Kf1 36. Kd7 Ke1 37. Ke6 Kf1 38. Kf5 Ke1 39. Kg4 Kf1 >>40. Kf3! Ke1 41. Qe2# >> >>moves marked with a ! are the only optimal move in that position. Any other >>move extends the mate or draws/loses... > >Thanks, >but nothing abnormal to be find here. >I still believe 1.Bc8 is better and will in the end give a shorter path to the >mate. >Uri Blass posted some while ago a position, where a computer, already a queen >ahead, happily sacrificed it to get a won pawn ending. >Something simliar might had happen here. Unfortunately i do not have enough >tablebases installed to check this out. > >Oliver I really can't answer that question. All I can say is that if Crafty says "mate in N" then it can be interpreted as "mate in at _most_ N moves and maybe less." To verify a mate in N, requires a search to depth 2N-1, which is not going to happen here. All I can really say is that either variation leads to a forced mate, not a potential draw...
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