Author: Jorge Pichard
Date: 15:23:59 06/07/00
Go up one level in this thread
On June 07, 2000 at 17:22:58, Simon Finn wrote: >On June 07, 2000 at 16:01:30, Charlie GOLD wrote: > >>On June 07, 2000 at 14:47:53, Enrique Irazoqui wrote: >> >>>On June 07, 2000 at 13:55:38, Simon Finn wrote: >>> >>>>On June 07, 2000 at 13:46:29, Simon Finn wrote: >>>> >>>>>>>Interesting position, but is black forced to take from h6 (gxh6)? May be -Kc8 >>>>>>>is better? I think that black loses in all variations. >>>>>> I think that black loses in all variations. >>>>> >>>>>Jouni's suggestion of 1..Kc8! looks good to me. >>>>>[D]8/1k4p1/3pP3/pP5P/8/8/1r5P/3K4 w - - 0 1 IF IT IS WHITE TO MOVE SURELY P-E7 WINS FOR WHITE and IF IT IS BLACK TO GO FIRST THEN BLACK WINS IN SEVERAL WAYS. CHARLIE > >It's White to move, but 1. e7 doesn't win. Black replies 1...Rb1+. > >Now 2. Kc2 allows 2... Re1 (and Black wins) while 2. Ke2 allows >2... Rxb5, when Black can answer 3. e8Q with Re5+ (and Black wins again). > >So White has to run up the d-file > >2. Kd2 Rb2+ 3. Kd3 Rb3+ 4. Kd4 Rb4+ 5. Kd5 Rxb5+ 6. Kxd6 Rb6+ > >Now 7. Kd7 doesn't work - Black replies 7... Rb1 8. e8Q Rd1+ 9. Ke7 Re1+ >and 7. Ke5 Rb1 is no better, so White has to run back down the d-file > >7. Kd5 Rb5+ 8. Kd4 Rb4+ 9. Kd3 Rb3+ > >Having captured the d6 pawn and returned, White can now cross the e-file > >10. Ke2 Rb2+ 11. Kf3 Rb3+ 12. Kf4 Rb4+ 13. Kf5 Rb5+ > >Now if White could only play 14. Kf6 Rb6+ 15. Kf7, he would win. >Unfortunately, the black pawn on g7 prevents this. This means that >he can make no futher progress (14. Kg6 Re5 wins for Black) so >he has to take the draw with 14. Kf4. > >That's why 1. h6! gxh6? 2. e7 wins for White - it allows White to >play Kf6 at the critical moment. > >>>>> >>>>>After 1. h6 Kc8 2. h7 Rxh2 3. e7 Kd7 4. b6 Rxh7 5. b7 >>>> >>>>Sorry - that should read: >>>> >>>>1. h6 Kc8 2. h7 Rxh2 3. e7 Kd7 4. b6 Rxh7 5 e8Q+ Kxe8 6. b7 >>> >>>I don't think it works. 1.h6 Kc8 2. e7 Kd7 3. h7 Rxh2 4. b6 Rxh7 5. e8Q+ Kxe8 6. >>>b7 Rh1+ 7. Kc2 Rh2+ 8. Kc3 Rh3+ 9. Kb2 Rh2+ 10. Ka3 then a4 and a5, and then the >>>b pawn promotes. > >You're absolutely right - that line wins for White. My mistake. > >>> >>>Enrique >>> >>> >>>>and the following move-numbers are all of-by-one >>>> >>>>> (or 1. h6 Kc8 2. e7 Kd7 3. h7 Rxh2 4. b6 Rxh7 5. b7) >>>>> >>>>>Black can draw in two different ways: >>>>> >>>>>Either 5... Rh1+ 6. Kc2 Rh2+ 7. Kc3 Rh3+ 8. Kc2 Rh2+ with perpetual check >>>>>(8. Kc4? Rh4+ and Rb4 wins for Black) >>>>> >>>>>Or 5... Rh6 6. b8Q+ Kf7 followed by ...d5 (unblocking the 6th rank) >>>>>with a fortress draw. > >This is inaccurate too. > >After 1. h6 Kc8 2. h7 Rxh2 3. e7 Kd7 4. b6 Rxh7 5 e8Q+ Kxe8 >6. b7 Rh6? 7. b8Q+ Kf7 White can blockade the d-pawn by 8. Qb7+ Kf8 9. Qd5! >(preventing ...d5), followed by capturing the a-pawn with his king, >bringing the king to d8 and (I think) finally using mating threats >to set up a zugzwang. > >However, I still think Black can draw - by playing 6...d5 instead of 6...Rh6 > >The critical line is now: > >1. h6 Kc8 2. h7 Rxh2 3. e7 Kd7 4. b6 Rxh7 5 e8Q+ Kxe8 6. b7 d5 7. b8Q+ Kf7 > >Black's rook is uncomfortable on h7, but if he has time to play Rh6 >the position will be a fortress draw. I don't see how White can >prevent this. For example: > >8. Qc7+ Kf8 9. Qc8+ Kf7 10. Qf5+ Kg8 11. Qxd5+ Kf8 12. Qf5+ Kg8 13. Qxa5 Rh6 > >and Black just keeps his king on one of the squares f7/f8/g8/h8/h7 >while moving his rook between h6 and f6. > >Simon Hiarcs may not be the best Analystical program, but Anand who has plenty of experience playing against Chess Programs, chose Hiarcs at the Advanced Chess Tournament as his analystical software of choice. Has anybody tried to solve it with Hiarcs yet? Pichard
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