Author: Robert Hyatt
Date: 09:24:53 10/14/98
Go up one level in this thread
On October 13, 1998 at 21:55:12, Mark Young wrote:
>On October 13, 1998 at 20:37:43, Robert Hyatt wrote:
>
>>On October 13, 1998 at 18:41:22, Mark Young wrote:
>>
>>>On October 13, 1998 at 17:35:34, Robert Hyatt wrote:
>>>
>>>>
>>>>After reading this thread, I decided to run a test myself. I started
>>>>off with 20 games of crafty vs crafty, white having KQ and no tablebases,
>>>>black having tablebases. At 20 seconds per move, this ended in 20 wins
>>>>for white which surprised me. I took several different positions (20 in
>>>>total) most of which were mate in 30 or greater and gave crafty 20 secs/move
>>>>using 1 cpu on my ALR. All wins. I didn't expect this.
>>>>
>>>>I then repeated this at 10 secs/move. All wins.
>>>>
>>>>I then repeated it at 5 secs/move. All wins. I was going to try 1 sec
>>>>but decided that to the computer, this is far easier than I thought. It
>>>>seems that the simple heuristic drive king to the edge, then to the
>>>>corner, is enough. It didn't play it perfectly, but it never slipped more
>>>>than 2 moves from optimal at any single move. And when it started off at
>>>>mate in 34, the "game" never went past 40 moves.
>>>>
>>>>So, I retract my original feeling, that KQ vs KR is hard with the KR
>>>>side having a database. It seems it is a "trivial" ending regardless of
>>>>having them or not.
>>>>
>>>>Most surprising...
>>>
>>>It happens to the best of us. I wonder if this simple idea of driving the king
>>>to the edge, then to the corner is what the Grandmaster's caught onto so quickly
>>>after only drawing the first few times, or did they find some other idea that
>>>also works.
>>
>>
>>No.. there's more to it than that... the main problem is the rook on the
>>opposite board, checking the king at the right time, also preventing the
>>king and queen from getting on the same rank or file for a skewer... and
>>the check lets the king "out" to the other side where it has to be done
>>again, and once it it out, the 50 move counter usually ends the game.
>>
>>I am utterly amazed that a 5 second search can solve this. Had you told
>>me this a year ago I'd have laughed. As it was I was skeptical. And when
>>I saw it I was *still* skeptical and was looking for a setup error in my
>>experiment.
>>
>>I still want to try at 1 sec / move however...
>>
>
>I was able to get fritz 5 to win KQ VS KR at 3 sec. a move average on my P II
>333. I thought my P II 400 might be able to do it a 1 or 2 sec a move but no
>dice. Fritz 5 wants to move almost instantly at 2 sec. a move or faster.
>
>
>>but this is definitely easier than KBN K now... to the computer, because
>>it takes a special piece/square table to win, since you have to drive to
>>the right corner as well...
ok... I have taken this as far as I want... and I hereby pronounce KQ vs
KR as *trivial*. I just finished the last test, 30 moves in 1 minute,
but this time *on my notebook* (a P5/233) and it still won 20 of 20 games,
although 1 was *very* close, winning the rook on move 50. Here is that
longest game, just for fun. But 2 secs a move on my notebook is like 1/3
of a second on my quad-6 machine, and I think it can do this even at 60/1
now. I thought it was hard. Damned program made that "thought" look
pretty foolish, however...
[Event "?"]
[Site "?"]
[Date "1998.10.14"]
[Round "?"]
[White "Crafty 15.21(no egtb)"]
[WhiteElo ""]
[Black "Crafty 15.21 (egtb)"]
[BlackElo ""]
[Result "1-0"]
[FEN "K6Q///3kr///// w "]
[SetUp "1"]
1. Kb7 Re2 2. Qd8+ Ke4 3. Qe8+ Kd3 4. Qb5+ Ke3 5. Kc6 Rd2 6. Qe5+
Kf3 7. Qc3+ Ke2 8. Kc5 Rd3 9. Qe5+ Kd2 10. Kc4 Rf3 11. Qe4 Re3
12. Qg2+ Ke1 13. Kd4 Rb3 14. Qg8 Ra3 15. Qg1+ Ke2 16. Qg2+ Ke1
17. Qc2 Rf3 18. Ke4 Rg3 19. Qc7 Rh3 20. Qc1+ Ke2 21. Qc2+ Kf1
22. Qd1+ Kf2 23. Qd2+ Kg3 24. Qg5+ Kf2 25. Qf5+ Kg2 26. Qg4+
Rg3 27. Qf4 Kh3 28. Qf7 Rg4+ 29. Ke5 Kg3 30. Qf5 Kh4 31. Qf2+
Kh3 32. Qf3+ Kh4 33. Qe3 Rg5+ 34. Kf4 Rg4+ 35. Kf5 Rg2 36. Qh6+
Kg3 37. Qf4+ Kh3 38. Qf3+ Kh2 39. Kf4 Kg1 40. Qe3+ Kf1 41. Qc1+
Ke2 42. Qc4+ Kf2 43. Qc5+ Ke2 44. Qh5+ Ke1 45. Qh1+ Kf2 46. Qd1
Rg8 47. Qd4+ Ke1 48. Qa1+ Ke2 49. Qa2+ Kd3 50. Qxg8 Kd4 51. Qd8+
Kc3 52. Ke4 Kc4 53. Qd4+ Kb5 54. Kd5 Ka6 55. Qb4 Ka7 56. Kc6 Ka6
57. Qb6# 1-0
Here is the "annotated" game, to show where the non-tablebase program
screwed up...
[Event "?"]
[Site "?"]
[Date "1998.10.14"]
[Round "?"]
[White "Crafty 15.21(no egtb)"]
[WhiteElo ""]
[Black "Crafty 15.21 (egtb)"]
[BlackElo ""]
[Result "1-0"]
[Annotator "Crafty v15.21"]
{annotating only white moves.}
{using a scoring margin of -1.00 pawns.}
{search time limit is 1.00}
1. Kb7
({2:Mat32} 1. Kb7)
1. ... Re2
2. Qd8+
({2:Mat31} 2. Qd8+)
2. ... Ke4
3. Qe8+
({2:Mat30} 3. Qe8+)
3. ... Kd3
4. Qb5+
({2:Mat29} 4. Qb5+)
4. ... Ke3
5. Kc6
({2:Mat28} 5. Kc6)
5. ... Rd2
6. Qe5+
({2:Mat28} 6. Qe5+)
({2:Mat27} 6. Qg5+)
6. ... Kf3
7. Qc3+
({2:Mat28} 7. Qc3+)
({2:Mat27} 7. Kc5)
7. ... Ke2
8. Kc5
({2:Mat27} 8. Kc5)
8. ... Rd3
9. Qe5+
({2:Mat26} 9. Qe5+)
9. ... Kd2
10. Kc4
({2:Mat25} 10. Kc4)
10. ... Rf3
11. Qe4
({2:Mat24} 11. Qe4)
11. ... Re3
12. Qg2+
({2:Mat23} 12. Qg2+)
12. ... Ke1
13. Kd4
({2:Mat22} 13. Kd4)
13. ... Rb3
14. Qg8
({2:Mat23} 14. Qg8)
({2:Mat21} 14. Qd5)
14. ... Ra3
15. Qg1+
({2:Mat22} 15. Qg1+)
15. ... Ke2
16. Qg2+
({2:Mat22} 16. Qg2+)
({2:Mat21} 16. Qh2+)
16. ... Ke1
17. Qc2
({2:Mat21} 17. Qc2)
17. ... Rf3
18. Ke4
({2:Mat20} 18. Ke4)
18. ... Rg3
19. Qc7
({2:Mat20} 19. Qc7)
({2:Mat19} 19. Qc5)
19. ... Rh3
20. Qc1+
({2:Mat19} 20. Qc1+)
20. ... Ke2
21. Qc2+
({2:Mat18} 21. Qc2+)
21. ... Kf1
22. Qd1+
({2:Mat18} 22. Qd1+)
({2:Mat17} 22. Qd2)
22. ... Kf2
23. Qd2+
({2:Mat17} 23. Qd2+)
23. ... Kg3
24. Qg5+
({2:Mat18} 24. Qg5+)
({2:Mat16} 24. Qe3+)
24. ... Kf2
25. Qf5+
({2:Mat17} 25. Qf5+)
({2:Mat17} 25. Qf4+)
25. ... Kg2
26. Qg4+
({2:Mat16} 26. Qg4+)
26. ... Rg3
27. Qf4
({2:Mat18} 27. Qf4)
({2:Mat15} 27. Qe2+)
27. ... Kh3
28. Qf7
({2:Mat20} 28. Qf7)
({2:Mat17} 28. Qd6)
28. ... Rg4+
29. Ke5
({2:Mat21} 29. Ke5)
({2:Mat19} 29. Kf5)
29. ... Kg3
30. Qf5
({2:Mat21} 30. Qf5)
({2:Mat20} 30. Qf1)
30. ... Kh4
31. Qf2+
({2:Mat20} 31. Qf2+)
31. ... Kh3
32. Qf3+
({2:Mat20} 32. Qf3+)
({2:Mat19} 32. Qe2)
32. ... Kh4
33. Qe3
({2:Mat20} 33. Qe3)
({2:Mat19} 33. Qe2)
33. ... Rg5+
34. Kf4
({2:Mat19} 34. Kf4)
34. ... Rg4+
35. Kf5
({2:Mat18} 35. Kf5)
35. ... Rg2
36. Qh6+
({2:Mat18} 36. Qh6+)
({2:Mat17} 36. Qf4+)
36. ... Kg3
37. Qf4+
({2:Mat17} 37. Qf4+)
37. ... Kh3
38. Qf3+
({2:Mat16} 38. Qf3+)
38. ... Kh2
39. Kf4
({2:Mat15} 39. Kf4)
39. ... Kg1
40. Qe3+
({2:Mat16} 40. Qe3+)
({2:Mat14} 40. Qc6)
40. ... Kf1
41. Qc1+
({2:Mat15} 41. Qc1+)
41. ... Ke2
42. Qc4+
({2:Mat15} 42. Qc4+)
({2:Mat14} 42. Qc6)
42. ... Kf2
43. Qc5+
({2:Mat15} 43. Qc5+)
({2:Mat14} 43. Qc6)
43. ... Ke2
44. Qh5+
({2:Mat14} 44. Qh5+)
44. ... Ke1
45. Qh1+
({2:Mat13} 45. Qh1+)
45. ... Kf2
46. Qd1
({2:Mat12} 46. Qd1)
46. ... Rg8
47. Qd4+
({2:Mat11} 47. Qd4+)
47. ... Ke1
48. Qa1+
({2:Mat10} 48. Qa1+)
48. ... Ke2
49. Qa2+
({2:Mat09} 49. Qa2+)
49. ... Kd3
50. Qxg8
({2:Mat08} 50. Qxg8)
({2:Mat08} 50. Qb3+)
50. ... Kd4
51. Qd8+
({2:Mat07} 51. Qd8+)
51. ... Kc3
52. Ke4
({2:Mat06} 52. Ke4)
52. ... Kc4
53. Qd4+
({2:Mat05} 53. Qd4+)
53. ... Kb5
54. Kd5
({2:Mat04} 54. Kd5)
54. ... Ka6
55. Qb4
({2:Mat03} 55. Qb4)
({2:Mat03} 55. Kc6)
55. ... Ka7
56. Kc6
({2:Mat02} 56. Kc6)
56. ... Kb7
57. Qb6# ((2:Mat01) 57. Qb6)
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