Author: Charles Worthington
Date: 23:58:02 04/12/03
Go up one level in this thread
On April 13, 2003 at 00:44:49, Robert Hyatt wrote: >On April 12, 2003 at 04:09:45, Jorge Pichard wrote: > >>On April 12, 2003 at 01:40:31, Robert Hyatt wrote: >> >>>On April 11, 2003 at 18:26:32, Jorge Pichard wrote: >>> >>>>Which Pawn should White push in order to win, please provide Analylis. >>>> >>>>[D]8/8/3P3P/5r2/2P5/2P4k/8/6K1 w - - 0 1 >>> >>>My human eye says c5. If Rxc5 then d7 and Rd5 is met by h7 and black is >>>pretty well hosed... >>> >>>The key is getting the rook to a square where it has to prevent >>>one pawn from queening from behind, because it can't stop both from >>>there, it needs to be on the first rank. >>> >>>Hence c5 to lure it away. >>> >>>cute position since Rc5 is not playable and anything else has trouble with >>>c6. >>> >>>I let crafty grind on this after I looked at it and sure enough, at depth >>>17 it fails high on c5. Takes 5 minutes to find it however, on my dual 2.8. >>> >>>Can you show me the Analysis on your dual 2.8 Ghz. > > > 17 14.62 1.28 1. d7 Rf8 2. c5 Kg3 3. h7 Ra8 4. Kf1 > Kf3 5. Ke1 Ke3 6. Kd1 Kd3 7. Kc1 Kxc3 > 8. Kd1 Kd3 9. h8=Q Rxh8 10. c6 > 17 5:18 ++ 1. c5!! > > > >> >>Yes c5! is the only winning move, but not too many programs can see this, not >>even after 5 Minutes. >> >>1. c5 Kg3 2. h7 Rf8 3. c6 Ra8 4. Kf1 Kf3 5. Ke1 Ke3 6. Kd1 Kd3 7. Kc1 Kxc3 8. >>Kd1 Kd3 9. Ke1 Ke3 10. Kf1 Kf3 11. Kg1 Kg3 12. h8=Q Rxh8 13. c7 it must be this >>pawn, since the b8 square is a vital one for Black's defense Ra8 14. Kf1 Kf3 15. >>Ke1 Ke3 16. Kd1 Kd3 17. Kc1 Kc3 18. Kb1 now there is no check on b8, so White >>wins, There will follow 19. d7 and the birth of a queen. >> >> >>If h7?? this is how Black King will stop it and mop the White pawns: >>1. h7 Rf8 2. c5 Kg4 3. c6 Kf5 4. d7 Ke6 etc... >> >> >>If d7?? this is how Black King will stop it and mop the White pawns: >>1. d7 Rf8 2. c5 Kg3 3. c6 Ra8 4. Kf1 Kf3 5. Ke1 Ke3 6. Kd1 Kd3 7. Kc1 Kxc3 8. >>Kb1 Rb8+ 9. Ka2 Ra8+ 10. Kb1 Rb8+ Draw >> >> Aparently I must not be testing this properly because Deep Fritz 7 selected 1.c5!! at once. What did I do wrong? I have posted the analysis below: 8/8/3P3P/5r2/2P5/2P4k/8/6K1 w - - 0 1 Analysis by Deep Fritz 7: Dual 3.06GHz Xeons 1.c5! = (0.03) Depth: 11/33 00:00:00 303kN, tb=28 1.c5! = (0.19) Depth: 11/33 00:00:00 355kN, tb=36 1.c5! ² (0.50) Depth: 11/33 00:00:00 435kN, tb=48 1.c5! ± (1.13) Depth: 11/33 00:00:01 539kN, tb=62 1.c5 Rxc5 2.d7 Rg5+ 3.Kf2 Rg8 4.Kf3 Rb8 5.h7 Kh4 6.Kf4 Kh5 +- (1.94) Depth: 11/33 00:00:02 841kN, tb=163 1.c5-- +- (1.66) Depth: 12/20 00:00:02 856kN, tb=194 1.c5 Rxc5 2.d7 Rg5+ 3.Kf2 Rg8 4.c4 Kg4 5.c5 Rf8+ 6.Ke3 ± (1.31) Depth: 12/25 00:00:02 1091kN, tb=278 1.c5! +- (1.59) Depth: 13/25 00:00:04 1648kN, tb=431 1.c5-- ± (1.31) Depth: 14/22 00:00:05 1791kN, tb=671 1.c5 Rxc5 2.d7 Rg5+ 3.Kf2 Rg8 4.h7 Rf8+ 5.Ke3 Kg4 6.Ke4 Kg5 7.Ke5 Kg6 8.Ke6 ± (1.13) Depth: 14/28 00:00:07 2507kN, tb=1155 1.h7! ± (1.16) Depth: 14/28 00:00:07 2926kN, tb=1181 1.h7! ± (1.31) Depth: 14/28 00:00:07 3095kN, tb=1188 1.h7-- ± (1.03) Depth: 15/29 00:00:08 3301kN, tb=1330 1.h7 Rf8 2.c5 Kg4 3.c6 Kf5 4.c4 Ke6 5.c5 Kd5 6.c7 Kc6 7.Kg2 ± (0.91) Depth: 15/31 00:00:08 3887kN, tb=1476 1.c5! ± (0.94) Depth: 15/31 00:00:11 5145kN, tb=2195 1.c5! ± (1.09) Depth: 15/31 00:00:12 6196kN, tb=2480 1.c5 Rxc5 2.d7 Rg5+ 3.Kf2 Rg8 4.h7 Rf8+ 5.Ke3 Kg4 6.Ke4 Kg5 7.Ke5 Kg6 8.Ke6 ± (1.13) Depth: 15/31 00:00:15 7272kN, tb=3238 1.c5! +- (1.41) Depth: 16/28 00:00:21 11645kN, tb=5101 1.c5-- ± (1.13) Depth: 17/30 00:00:32 17372kN, tb=9060 1.c5 Kg3 2.h7 Rf8 3.c6 Ra8 4.Kf1 Kf3 5.Ke1 Ke3 6.Kd1 Kd3 7.Kc1 Kxc3 8.Kd1 Kd3 9.Ke1 = (0.00) Depth: 17/31 00:00:36 18952kN, tb=10387 1.c5! ² (0.28) Depth: 18/33 00:00:53 27238kN, tb=17490 1.c5! ² (0.56) Depth: 18/34 00:00:59 38951kN, tb=21517 1.c5! ± (1.13) Depth: 18/34 00:01:06 55778kN, tb=25781 1.c5! +- (1.41) Depth: 19/37 00:01:42 102091kN, tb=42198 (Worthington, MyTown 13.04.2003) It took 11 seconds to uncover it. Charles >>>> >>>>------------------------------------------------------------------------------- >>>>This is another position of Reciprocal Zugzwang: If White is to play, then he >>>>can only draw, but if Black is to play, he loses. In other words, any move by >>>>either side weakens his position to the extend of worsening the result of the >>>>game! >>>> >>>>[D]1R4br/8/8/8/8/4K3/k5P1/8 w - - 0 1 >>> >>>Crafty says g3 is a dead draw.
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