Author: Vincent Diepeveen
Date: 11:29:32 07/18/02
Go up one level in this thread
On July 18, 2002 at 14:17:30, Dieter Buerssner wrote:
yace is right here. qxa3 is like +10 for white, but it takes
either mating extensions or a huge depth to see it that high in
score.
>On July 18, 2002 at 09:22:00, Uri Blass wrote:
>
>>You remember correctly and the right line is Ba3 Qxa3 Nh5+
>
>Yace does not agree with your "right line" after some time.
>
>K6-2 475, in the background with about 60% CPU time.
>
>[Ba3 also found earlier with draw score]
> 15690097 3:02.7 0.00 11t 30. Ne2 Na5 31. Ba3 Qxa3 32. Qc7+ Kh6 33. Qf4+
> Kg7 34. Qc7+ {-420}
> 27202864 5:19.2 0.01 11t+ 30. Ba3 Qxa3 31. Nh5+ gxh5 32. Qg5+ Kf8 33.
> Qxf6+ Kg8 34. Qf7+ Kh8 35. g3 Qc1+ 36. Kg2 Qc2+
> 37. Kh3 Qxc3
> 28641052 5:34.9 0.41 11++ 30. Ba3 Qxa3 31. Nh5+ gxh5 32. Qg5+ Kf8 33.
> Qxf6+ Kg8 34. Qf7+ Kh8 35. g3 Qc1+ 36. Kg2 Qc2+
> 37. Kh3 h6 38. Qf8+ Kh7 39. e7 Qe4 40. e8=Q h4
> {501}
> 50280895 9:53.0 0.85 11t 30. Ba3 Qe8 31. Qc7+ Kg8 32. Be7 Ng4 33. Qxa7
> Nd2 34. Bg5 Nb1 35. Qd7 Qxd7 {-991}
> 52940978 10:21.9 0.85 11. 30. Ba3 Qe8 31. Qc7+ Kg8 32. Be7 Ng4 33. Qxa7
> Nd2 34. Bg5 Nb1 35. Qd7 Qxd7 {-991}
> 63514652 12:28.9 1.25 12++ 30. Ba3 Qe8 31. Qc7+ Kg8 32. Be7 Ng4 33. Qd7
> Qa8 34. Bf6 Nf2 35. Kxf2 Qf8 36. e7 Kf7 {270}
> 80462007 16:05.7 2.25 12++ 30. Ba3 Qe8 31. Qc7+ Kg8 32. Be7 Ng4 33. Qd7
> Qa8 34. Bf6 Nf2 35. Kxf2 Qf8 36. e7 Kf7 {270}
> 93318518 18:28.4 2.73 12t 30. Ba3 Qe8 31. Qc7+ Kg8 32. Be7 Kg7 33. Bd8+
> Kf8 34. Bxf6H Qxe6H 35. Bg7+H Ke8H {HT} {190}
>
>>Ba3 is easy to find because of the draw and the real test position is to
>>find Nh5+ in the following position:
>>
>>8/p5kp/1p2Pnp1/3pQ3/2pP4/qnP3N1/6PP/6K1 w - - 0 2
>>
>>It is not very hard to fail high on Nh5+ but solving the fail high seems to be a
>>very hard problem for movei on p800(16 mbytes hash tables) and it's branching
>>factor is not good.
>
>I also get a bad branching factor here, when Nh5 fails high. But it is not too
>surprising, IMO.
>
> 948176 8.477 0.00 8t 2. Qc7+ Kh8 3. Qb8+ Kg7 4. Qc7+ {-420}
> 1841535 17.406 0.01 8t+ 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Qc1+ 7. Kg2 Qb2+ 8. Kh3 h6 9. Qf8+
> Kh7 10. e7 Qxc3 11. e8=Q Nxd4 {341}
> 1888582 18.853 0.40 8++ 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Qc1+ 7. Kg2 Qb2+ 8. Kh3 h6 9. Qf8+
> Kh7 10. e7 Qxc3 11. e8=Q Nxd4 {341}
> 2215451 22.534 1.40 8++ 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Qc1+ 7. Kg2 Qb2+ 8. Kh3 h6 9. Qf8+
> Kh7 10. e7 Qxc3 11. e8=Q Qc1 {421}
> 3656104 35.942 4.54 8t 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Nxd4 7. e7 Qc1+ 8. Kg2 Qc2+ 9. Kh3
> Qf5+ 10. Qxf5 Nxf5 11. e8=Q+ Kg7 12. Qd7+ Kf6
> 13. Qxa7 {501}
> 3678733 36.196 4.54 8. 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Nxd4 7. e7 Qc1+ 8. Kg2 Qc2+ 9. Kh3
> Qf5+ 10. Qxf5 Nxf5 11. e8=Q+ Kg7 12. Qd7+ Kf6
> 13. Qxa7 {501}
> 5130597 51.115 4.75 9t 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Nxd4 7. e7 Qc1+ 8. Kg2 Qc2+ 9. Kh3
> Qf5+ 10. Qxf5 Nxf5 11. e8=Q+ Kg7 12. Qe6 Nh6
> 13. Qe7+ Nf7H {HT} {421}
> 6238514 1:00.5 4.75 9. 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Nxd4 7. e7 Qc1+ 8. Kg2 Qc2+ 9. Kh3
> Qf5+ 10. Qxf5 Nxf5 11. e8=Q+ Kg7 12. Qe6 Nh6
> 13. Qe7+ Nf7 {HT} {421}
> 7702096 1:14.3 5.15 10++ 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Nxd4 7. e7 Qc1+ 8. Kg2 Qc2+ 9. Kh3
> Qf5+ 10. Qxf5 Nxf5 11. e8=Q+ Kg7 12. Qe6 Nh6
> 13. Qxd5 a6 {HT} {501}
> 11492539 1:52.6 5.15 10t 2. Nh5+ gxh5 3. Qg5+ Kh8H 4. Qxf6+H Kg8H 5.
> Qf7+H Kh8H 6. g3H Nxd4H 7. e7H Qc1+H 8. Kg2H
> Qc2+H 9. Kg1H Ne2+H 10. Kh1H Nxg3+H 11. hxg3H
> Qe4+H 12. Kh2H Qe2+H 13. Kh3H Qg4+H 14. Kg2H
> {HT} {-240}
> 16171881 2:34.7 5.15 10. 2. Nh5+ gxh5 3. Qg5+ Kh8 4. Qxf6+ Kg8 5. Qf7+
> Kh8 6. g3 Nxd4 7. e7 Qc1+ 8. Kg2 Qc2+ 9. Kg1
> Ne2+ 10. Kh1 Nxg3+ 11. hxg3 Qe4+ 12. Kh2 Qe2+
> 13. Kh3 Qg4+ 14. Kg2 {HT} {-240}
>
>Interestingly, Nh5 is found at depth 8 here, which would suggest, that in the
>original position, a fail high at depth 10 for Ba3 could be expected. But it was
>only at depth 11 ...
>
>Regards,
>Dieter
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