Author: Dieter Buerssner
Date: 11:48:17 12/20/02
Go up one level in this thread
On December 19, 2002 at 19:39:56, Roy Eassa wrote:
>White to move & win
> 7k/5r2/6PK/6P1/8/8/5P1R/8 w - - 0 1
>
>7k/5r2/6PK/6P1/8/8/5P1R/8 w - - 0 1
>
>1.g7+!
>
> [1.Kh5 Rf4 only draws]
>
>1...Kg8
>
> [1...Rxg7 2.Rh5 Kg8
> (2...Rf7 3.Kg6+ Kg8 4.Rh8+ +-)
> 3.g6 Rd7 4.Ra5 +-]
>
>2.Rh3! Rf3 3.Rg3! Rxf2
>
> [3...Rf4 4.Re3 Rh4+ 5.Kg6 Re4 6.Kf5 Rc4 7.Re7 +-]
>
>4.Ra3 Rh2+ 5.Kg6 Ra2 6.Rf3 Ra6+ 7.Rf6 Rb6 8.Kh6! Rb8 9.Rf8+ +-
>
> [9.g6 also works]
With a very long search, Yace can find a mate score (P4 2.53 GHz)
298868 1.154 2.91 12t 1. Kh5 Rf4 2. f3 Kg8 3. Rf2 Kg7 {HT}
342068 1.430 2.92 12t+ 1. g7+ Rxg7 2. Rh5 Kg8 3. g6 Rc7 4. f4 Rc8
404497 1.555 3.17 12t 1. g7+ Rxg7 2. Rh5 Kg8 3. g6 Rc7 4. Re5 Rc8 5.
f4 Rd8 6. f5 Rd4H {HT}
445971 1.688 3.17 12. 1. g7+ Rxg7 2. Rh5 Kg8 3. g6 Rc7 4. Re5 Rc8 5.
f4 Rd8 6. f5 Rd4
726109 2.628 3.31 13t 1. g7+ Rxg7 2. Rh5 Rc7 3. g6 Rc1 4. Kg5+ Kg8 5.
f4 Rg1+ 6. Kf6 Rb1 7. f5 Rb6+ 8. Kg5H Rb3H {HT}
997348 3.275 3.31 13. 1. g7+ Rxg7 2. Rh5 Rc7 3. g6 Rc1 4. Kg5+ Kg8 5.
f4 Rg1+ 6. Kf6 Rb1 7. f5 Rb6+ 8. Kg5 Rb3
1224233 3.852 3.36 14t 1. g7+ Rxg7 2. Rh5 Rc7 3. f4 Kg8 4. f5 Rh7+H 5.
Kg6H Rg7+H 6. Kf6H Rb7H 7. g6H Rb6+H 8. Kg5H
Rb5H 9. Rh7H Kf8H 10. Rd7H Re5H {160}
1311651 4.059 3.36 14. 1. g7+ Rxg7 2. Rh5 Rc7 3. f4 Kg8 4. f5 Rh7+ 5.
Kg6 Rg7+ 6. Kf6 Rb7 7. g6 Rb6+ 8. Kg5 Rb5 9.
Rh7 Kf8 10. Rd7 Re5 {160}
1797616 5.607 3.37 15t 1. g7+ Rxg7 2. Rh5 Rb7 3. f4 Kg8 4. g6H Rb1H 5.
f5H Rb6H {HT}
1938763 5.961 3.37 15. 1. g7+ Rxg7 2. Rh5 Rb7 3. f4 Kg8 4. g6 Rb1 5.
f5 Rb6
3040748 9.379 3.73 16t 1. g7+ Rxg7 2. Rh5 Rb7 3. f4 Kg8 4. g6 Rb1 5.
Rd5 Rh1+ 6. Kg5 Rc1 7. f5 Kf8 8. f6 Rg1+ 9. Kf5
Rf1+ 10. Ke6H Re1+H 11. Re5H Rg1H 12. Rg5H {160}
3379133 10.702 3.73 16. 1. g7+ Rxg7 2. Rh5 Rb7 3. f4 Kg8 4. g6 Rb1 5.
Rd5 Rh1+ 6. Kg5 Rc1 7. f5 Kf8 8. f6 Rg1+ 9. Kf5
Rf1+ 10. Ke6 Re1+ 11. Re5 Rg1 12. Rg5 {160}
7462566 22.858 4.12 17t 1. g7+ Kg8 2. Rh3 Rf4 3. Re3H Rh4+H 4. Kg6H
Re4H 5. Kf5H Rb4H 6. Re8+H Kxg7H 7. Re7+H Kg8H
8. g6H {HT}
7856815 24.451 4.12 17. 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kf5 Rb4 6. Re8+ Kxg7 7. Re7+ Kg8 8. g6
12907045 38.616 4.21 18t 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kf5 Rb4 6. Re7 Rb6 7. f4 Rb5+ 8. Kf6 Rb6+ 9.
Re6H Rb8H 10. f5H Rd8H 11. Re7H Rd5H {HT}
13468504 39.806 4.21 18. 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kf5 Rb4 6. Re7 Rb6 7. f4 Rb5+ 8. Kf6 Rb6+ 9.
Re6 Rb8 10. f5 Rd8 11. Re7 Rd5
55586138 2:39.8 4.56 19t 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kf5 Rb4 6. Re7 Rb6 7. f4 Ra6 8. Ke5 Rc6 9. f5
Rc5+ 10. Ke6 Rc6+ 11. Kd7 Ra6 12. f6H Ra7+H 13.
Ke6H Ra6+H 14. Ke5H Rc6H 15. Kf5H Kh7H {240}
57074791 2:42.7 4.56 19. 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kf5 Rb4 6. Re7 Rb6 7. f4 Ra6 8. Ke5 Rc6 9. f5
Rc5+ 10. Ke6 Rc6+ 11. Kd7 Ra6 12. f6 Ra7+ 13.
Ke6 Ra6+ 14. Ke5 Rc6 15. Kf5 Kh7 {240}
88426017 3:58.9 4.96 20++ 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kf5 Rb4 6. Re7 Rb6 7. f4 Ra6 8. Ke5 Rc6 9. f5
Kh7 10. f6 Rc5+ 11. Ke6 Rc1 12. Re8 Rc6+ 13.
Ke7 Rc2
90195208 4:01.4 4.96 20t 1. g7+ Kg8 2. Rh3 {HT}
91369066 4:05.7 4.96 20. 1. g7+ Kg8 2. Rh3
117045976 5:05.4 5.36 21++ 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kf5 Rb4 6. g6 Kxg7 7. f4 Kf8 8. Kg5 Rb5+ 9. f5
Rb8 10. f6 Rb5+ 11. Kf4 Rb4+ 12. Kf5 Rb8 13.
Re7 Kg8 14. g7 Kh7 15. g8=Q+ Kh6 {1081}
147447941 6:39.5 6.36 21++ 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kh5 Rf4 6. Re7 Kh7 7. g8=Q+ Kxg8 8. Kg6 Kf8 9.
Re6 Rh4 10. f4 Rh8 11. f5 Rg8+ 12. Kh5 Rh8+ 13.
Rh6 Rg8 14. f6 Kf7 15. Rh7+ Ke6 16. f7 Rf8 17.
g6 Kf5 18. g7 Rd8 19. f8=Q+ Ke4 {1081}
181993329 8:00.4 6.36 21t 1. g7+ Kg8 2. Rh3 {HT}
188455191 8:16.2 6.36 21. 1. g7+ Kg8 2. Rh3
221336647 9:27.6 6.76 22++ 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kh5 Rc4 6. Re7 Kh7 7. g8=Q+ Kxg8 8. Rb7 Ra4 9.
Kh6 Kf8 10. Rb8+ Ke7 11. g6 Ra6 12. Kh7 Ra1 13.
g7 Rh1+ 14. Kg6 Rg1+ 15. Kf5 Rc1 16. g8=Q Kd6
{1081}
414344730 20:39.9 6.77 22t 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+H 4. Kg6H Re4H
5. Kh5H Rc4H 6. Rb3H {HT}
424232206 21:27.4 6.77 22. 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kh5 Rc4 6. Rb3
489151249 25:10.0 7.17 23++ 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kh5 Rc4 6. Rb3 Kxg7 7. Rb7+ Kf8 8. g6 Rc1 9.
Kg5 Rc4
560989576 29:05.2 8.17 23++ 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kh5 Rc4 6. Re7 Kh7 7. g6+ Kg8 8. Re8+ Kxg7 9.
Re7+ Kg8 10. Kh6 Rh4+ 11. Kg5 Rh2 12. f4 Rb2
13. f5 Kf8 14. f6 Rg2+ 15. Kh5 Rh2+ 16. Kg4 Rh1
17. g7+ Kg8 18. Re8+ Kh7
669668661 37:46.5 13.17 23++ 1. g7+ Kg8 2. Rh3 Rf4 3. Re3 Rh4+ 4. Kg6 Re4 5.
Kh5 Rc4 6. Re7 Kh7 7. g6+ Kg8 8. Re8+ Kxg7 9.
Re7+ Kg8 10. Kh6 Rh4+ 11. Kg5 Rh2 12. f4 Rb2
13. f5 Kf8 14. f6 Rg2+ 15. Kf5 Rf2+ 16. Ke5
Re2+ 17. Kd4 Rd2+ 18. Ke3 Rd8 19. g7+ Kg8 20.
f7+ Kh7 21. g8=Q+ Kh6 22. f8=Q+ Kh5 {2002}
[this fail high takes a very loooong time ...]
1103398983 6:00:01 Mat26 23t 1. g7+ Kg8 2. Rh3 Rf3 3. Rg3 Rf4 4. Re3 Rh4+ 5.
Kg6H Re4H 6. Kf5H Ra4H 7. Re7H Kh7H 8. f4H {HT}
{240}
1141639780 6:03:31 Mat26 23. 1. g7+ Kg8 2. Rh3 Rf3 3. Rg3 Rf4 4. Re3 Rh4+ 5.
Kg6 Re4 6. Kf5 Ra4 7. Re7 Kh7 8. f4 {HT} {240}
Unfortunately, most of the line is hidden because of the HT. If I follow the
line above, I get (the mate got one shorter):
110900744 9:16.4 -Mat17 17. 8...Kg8 9. Ke5 Ra5+ 10. Kf6 Ra8 11. f5 Ra6+ 12.
Re6 Ra8 13. Kg6 Ra6 14. Rf6 Rxf6+ 15. Kxf6
{EGTB} 15...Kh7 16. Ke6 Kxg7 17. f6+! Kh7 18.
f7! Kg7! 19. Ke7! Kg6! 20. f8=Q! Kxg5 21. Qf3
Kh4! 22. Qe3 Kh5 23. Qg3! Kh6 24. Kf6! Kh7 25.
Qg7#! {-1001}
After 6...Rc4 of your line instead of Ra4:
357 0.026 Mat18 17. 7. Re7 Rc6 8. Ke5 Rc8 9. Kf6 Rd8 10. Re6 Kh7
11. f4 Rb8 12. Kf7 Rb7+ 13. Re7 Rxe7+ 14. Kxe7
{EGTB} 14...Kxg7 15. f5! Kh7! 16. f6! Kg6! 17.
f7! Kxg5 18. f8=Q! Kg4! 19. Qf2 Kg5! 20. Qf3
Kh4! 21. Qe3 Kh5 22. Qg3! Kh6 23. Kf6! Kh7 24.
Qg7#! {1001}
After 3...Rxf2 of your main line:
2934258 20.461 Mat20 22. 4. Re3 Rh2+ 5. Kg6 Re2 6. Rf3 Re6+ 7. Rf6 Rxf6+
{EGTB} 8. Kxf6!! Kh7 9. g8=Q+ Kxg8 10. Kg6!!
Kf8! 11. Kh7! Ke8 12. g6! Ke7 13. g7! Kd6! 14.
g8=Q Kc5! 15. Qe8 Kd5 16. Qa4 Ke5 17. Qc4 Kf5
18. Qd4 Kg5! 19. Qe4 Kh5 20. Kg7! Kg5 21. Kf7!
Kh5! 22. Kf6! Kh6 23. Qh4# {1001}
Of course, the mate lenght should not be considered as shortest mates possible.
! means, only move that yields (this time really) the best play, !! means, only
move that wins.
You mentioned, that the first plies should be correct. I think, this is not so
easy to judge. Baron and CM chose 2...Rf4 instead of 2...Rf3. Yace the same at
reasonable thinking time. I think, in the case of the defender move, one just
has to look, what the engine would do with the alternate defense to judge, and
it is very likely (considering the high score shown) that the find the correct
moves in this specific case.
Regards,
Dieter
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