Author: Robert Hyatt
Date: 19:21:15 12/30/03
Go up one level in this thread
On December 30, 2003 at 13:33:57, Michael Henderson wrote: > >Crafty v 19.2 gives the following analysis for Fine #70, starting at ply 36: > >8/k7/3p4/p2P1p2/P2P1P2/8/8/K7 w - - 0 1 > > depth time score > > 36 1.25 5.17 1. Kb1 Kb7 2. Kc1 Kc7 3. Kd1 Kc8 4. > Kd2 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 > Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 > 11. Kg5 Kg7 12. Kxf5 Kf7 13. Kg5 <HT> > 36-> 1.25 5.17 1. Kb1 Kb7 2. Kc1 Kc7 3. Kd1 Kc8 4. > Kd2 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 > Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 > 11. Kg5 Kg7 12. Kxf5 Kf7 13. Kg5 <HT> > 37 1.27 -- 1. Kb1 > 37 1.45 4.68 1. Kb1 Kb7 2. Kc1 Kc7 3. Kd1 Kc8 4. > Kd2 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 > Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 > 11. Kg5 Kg7 12. Kxf5 Kf7 13. Kg5 Kg7 > 14. f5 Kf7 15. f6 Kf8 16. Kg4 Kg8 17. > Kf4 Kf8 18. Ke4 Ke8 19. Kf5 > 37-> 1.45 4.68 1. Kb1 Kb7 2. Kc1 Kc7 3. Kd1 Kc8 4. > Kd2 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 > Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 > 11. Kg5 Kg7 12. Kxf5 Kf7 13. Kg5 Kg7 > 14. f5 Kf7 15. f6 Kf8 16. Kg4 Kg8 17. > Kf4 Kf8 18. Ke4 Ke8 19. Kf5 > 38 2.59 ++ 1. Kb1!! > 38 10.26 6.71 1. Kb1 Kb7 2. Kc1 Kb8 3. Kc2 Kb7 4. > Kc3 Kc7 5. Kd3 Kb7 6. Ke3 Kc7 7. Kf3 > Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 > 11. Kg5 Kg7 12. Kxf5 Kf7 13. Kg5 <HT> > 38-> 10.26 6.71 1. Kb1 Kb7 2. Kc1 Kb8 3. Kc2 Kb7 4. > Kc3 Kc7 5. Kd3 Kb7 6. Ke3 Kc7 7. Kf3 > Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 > 11. Kg5 Kg7 12. Kxf5 Kf7 13. Kg5 <HT> > 39 10.49 -- 1. Kb1 > > > >I will take the ply 36 analysis to illustrate the specific problem: > > depth time score > > 36 1.25 5.17 1. Kb1 Kb7 2. Kc1 Kc7 3. Kd1 Kc8 4. > Kd2 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 > Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 > 11. Kg5 Kg7 12. Kxf5 Kf7 13. Kg5 <HT> > >36 plies is more than enough plies to see the winning capture Kxf5. The key > >position is after 4. Kd2. Black has a choice of playing either Kc7 or Kd7. > >Kd7 holds off the winning capture (Kxf5) two more plies than Kc7. Crafty > >wants to play 4. ...Kc7 in the analysis. Here is the key position FEN: > >2k5/8/3p4/p2P1p2/P2P1P2/8/3K4/8 b - - 0 1 >Crafty gives this analysis starting from the position after 4. Kd2 > > > depth time score > > 36 1:02 7.10 1. ... Kd7 2. Kc3 Kc7 3. Kd3 Kb6 4. > Ke3 Kc7 5. Kf3 Kd7 6. Kg3 Ke7 7. Kh4 > Kf6 8. Kh5 Kf7 9. Kg5 Kg7 10. Kxf5 > Kf7 11. Ke4 Kf6 12. Kd3 Kf5 13. Kc4 > Kxf4 14. Kb5 Ke4 15. Kxa5 Kxd5 16. > Kb5 Kxd4 17. a5 d5 18. Kb6 Kd3 19. > a6 > 36-> 1:02 7.10 1. ... Kd7 2. Kc3 Kc7 3. Kd3 Kb6 4. > Ke3 Kc7 5. Kf3 Kd7 6. Kg3 Ke7 7. Kh4 > Kf6 8. Kh5 Kf7 9. Kg5 Kg7 10. Kxf5 > Kf7 11. Ke4 Kf6 12. Kd3 Kf5 13. Kc4 > Kxf4 14. Kb5 Ke4 15. Kxa5 Kxd5 16. > Kb5 Kxd4 17. a5 d5 18. Kb6 Kd3 19. > a6 > >So, the from Fine #70, crafty gives this line after 4.Kd2: > >4. ... Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 > >11. Kg5 Kg7 12. Kxf5 > >while, starting from the position after 4.Kd2, we are given this line: > >4. ... Kd7 5. Kc3 Kc7 6. Kd3 Kb6 7. Ke3 Kc7 8. Kf3 Kd7 9. Kg3 Ke7 10. Kh4 Kf6 > >11. Kh5 Kf7 12. Kg5 Kg7 13. Kxf5 > >I would think that black would try to delay the loss two more plies from Fine >#70 with Kd7, or does it see Kc7 because black will lose anyway? > >thx for reading, >Michael Henderson The problem with your comment is that it is contrary to the way the program works. Any program knows to take a mate in 20 plies over a mate in 24 plies. But a program will _not_ understand the difference between winning a pawn in 20 plies and 24 plies, and therefore either is considered _exactly_ the same from the program's alpha/beta search point of view...
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