Author: Bernhard Bauer
Date: 23:17:11 03/10/99
Go up one level in this thread
On March 11, 1999 at 02:03:04, Peter Kappler wrote:
>On March 10, 1999 at 23:08:47, blass uri wrote:
>
>>
>>On March 10, 1999 at 22:59:37, Robert Hyatt wrote:
>>
>>>On March 10, 1999 at 22:49:00, Robert Hyatt wrote:
>>>
>>>>On March 10, 1999 at 21:54:51, blass uri wrote:
>>>>
>>>>>
>>>>>On March 10, 1999 at 21:16:33, Robert Hyatt wrote:
>>>>>
>>>>>>On March 10, 1999 at 02:33:14, Peter Kappler wrote:
>>>>>>
>>>>>>>
>>>>>>>8/8/4kpp1/3p1b2/p6P/2B5/6P1/6K1 b - - bm Bh3; id "Topalov-Shirov Linares 98";
>>>>>>>
>>>>>>>
>>>>>>>Does everybody remember this game? It's from last year's Linares tournament,
>>>>>>>where Shirov played a shocking bishop sacrifice in the endgame and won
>>>>>>>brilliantly. I believe that post-mortem analysis proved it was the only way to
>>>>>>>win. (Please correct me if this is wrong)
>>>>>>>
>>>>>>>I watched this game live on ICC with dozens of others, and we were all quite
>>>>>>>impressed with Shirov's powers of calculation.
>>>>>>>
>>>>>>>This *should* be an extremely difficult problem for computers - but I'm sure
>>>>>>>somebody will tell me that Hiarcs or some other commercial program can solve it
>>>>>>>in 10 seconds.
>>>>>>>
>>>>>>>Just curious...
>>>>>>>
>>>>>>>--Peter
>>>>>>
>>>>>>
>>>>>>I ran this two ways.. First from the original position to see what crafty would
>>>>>>play with no 'urging' by me:
>>>>>>
>>>>>> 12-> 6.37 2.61 1. ... a3 2. Kf2 Bc2 3. g4 Bd1 4. h5
>>>>>> gxh5 5. gxh5 Bxh5 6. Ke3 a2 7. Kd4
>>>>>> Bd1 8. Ba1 f5
>>>>>> 13 11.78 2.62 1. ... a3 2. Kf2 Bc2 3. g4 Bd1 4. h5
>>>>>> gxh5 5. gxh5 Bxh5 6. Ke3 a2 7. Bb2
>>>>>> Bg6 8. Kd4 Be4 9. Ba1
>>>>>> 13-> 13.87 2.62 1. ... a3 2. Kf2 Bc2 3. g4 Bd1 4. h5
>>>>>> gxh5 5. gxh5 Bxh5 6. Ke3 a2 7. Bb2
>>>>>> Bg6 8. Kd4 Be4 9. Ba1
>>>>>> 14 34.53 2.46 1. ... a3 2. Kf2 Bc2 3. Ba1 Kf5 4.
>>>>>> Ke3 Be4 5. g3 a2 6. Kf2 Bc2
>>>>>> 14-> 45.46 2.46 1. ... a3 2. Kf2 Bc2 3. Ba1 Kf5 4.
>>>>>> Ke3 Be4 5. g3 a2 6. Kf2 Bc2
>>>>>> 15 1:08 2.46 1. ... a3 2. Kf2 Bc2 3. Ba1 Kf5 4.
>>>>>> Ke3 Be4 5. g3 a2 6. Kf2 Bc2
>>>>>> 15-> 1:24 2.46 1. ... a3 2. Kf2 Bc2 3. Ba1 Kf5 4.
>>>>>> Ke3 Be4 5. g3 a2 6. Kf2 Bc2
>>>>>> 16 2:55 2.37 1. ... a3 2. Kf2 Bc2 3. Ke3 a2 4. g3
>>>>>> Kf5 5. Kd4 Be4 6. Kc5 Kg4 7. Bxf6 Kxg3
>>>>>> 8. Kd6 Kg4
>>>>>> 16-> 3:59 2.37 1. ... a3 2. Kf2 Bc2 3. Ke3 a2 4. g3
>>>>>> Kf5 5. Kd4 Be4 6. Kc5 Kg4 7. Bxf6 Kxg3
>>>>>> 8. Kd6 Kg4
>>>>>> 17 8:25 2.42 1. ... a3 2. Kf2 a2 3. Ke2 Be4 4. Kf2
>>>>>> Kf5 5. g3 Bb1 6. Ke3 Bc2 7. Kd4 Be4
>>>>>> 8. Kc5 Kg4 9. Bxf6
>>>>>>
>>>>>>
>>>>>>so it likes a3 thru any depth it might get in a real tournament setting.
>>>>>>
>>>>>>
>>>>>>I then played Bh3 and let it search for white:
>>>>>>
>>>>>> 16-> 49.18 0.56 2. gxh3 Kf5 3. Kf2 Kf4 4. Bxf6 a3 5.
>>>>>> Bc3 Ke4 6. Ba1 Kf4 7. Bh8
>>>>>> 17 1:14 0.68 2. gxh3 Kf5 3. Kf2 Kf4 4. Bxf6 a3 5.
>>>>>> Bc3 Ke4 6. Ke2 Kf4 7. Kd3 Kg3 8. Bf6
>>>>>> a2 9. Kc2 Kf4 10. Kb3 Kf5
>>>>>> 17-> 1:22 0.68 2. gxh3 Kf5 3. Kf2 Kf4 4. Bxf6 a3 5.
>>>>>> Bc3 Ke4 6. Ke2 Kf4 7. Kd3 Kg3 8. Bf6
>>>>>> a2 9. Kc2 Kf4 10. Kb3 Kf5
>>>>>> 18 1:56 -- 2. gxh3
>>>>>> 18 2:39 0.00 2. gxh3 Kf5 3. Kf2 Ke4 4. Bxf6 a3 5.
>>>>>> h5 gxh5 6. Ba1 d4 7. Ke2 h4 8. Kd2
>>>>>> Kf4 9. Bxd4 Kg3 10. Bc3 Kxh3
>>>>>> 18-> 3:26 0.00 2. gxh3 Kf5 3. Kf2 Ke4 4. Bxf6 a3 5.
>>>>>> h5 gxh5 6. Ba1 d4 7. Ke2 h4 8. Kd2
>>>>>> Kf4 9. Bxd4 Kg3 10. Bc3 Kxh3
>>>>>> 19 4:37 0.00 2. gxh3 Kf5 3. Kf2 Ke4 4. Bxf6 a3 5.
>>>>>> h5 gxh5 6. Ba1 d4 7. Ke2 h4 8. Kd2
>>>>>> Kf4 9. Bxd4 Kg3 10. Bc3 Kxh3
>>>>>> 19-> 5:24 0.00 2. gxh3 Kf5 3. Kf2 Ke4 4. Bxf6 a3 5.
>>>>>> h5 gxh5 6. Ba1 d4 7. Ke2 h4 8. Kd2
>>>>>> Kf4 9. Bxd4 Kg3 10. Bc3 Kxh3
>>>>>>
>>>>>>which is right interesting, because notice this runs into the 5 piece
>>>>>>tablebases and says _draw_.
>>>>>>
>>>>>>question is, now, does Bh3 really make sense? This seems to say "no".
>>>>>>
>>>>>>interesting...
>>>>>Did you let crafty to play against itself.
>>>>>after 2.gxh3 Kf5 3.Kf2 Ke4 4.Bxf6
>>>>>crafty16.5 as an engine for Junior5(no tablebases) prefers 4...d4 with
>>>>>evaluation -6.01 at depth 18 and -6.02 at depth 19
>>>>>
>>>>>I believe that crafty needs more time to see the win after Bh3.
>>>>>
>>>>>I do not remember the game but I remember that I analyzed it with a computer and
>>>>>did not see a draw for white.
>>>>>
>>>>>Uri
>>>>
>>>>
>>>>I will check deeper.. but note that after Bh3, it reaches the endgame databases
>>>>and with white on move, it claims white can force a dead draw. I don't see any
>>>>reason it would change to let black do more, after forcing a path to a tablebase
>>>>draw...
>>>>
>>>>And note that crafty is using _all_ the 5 piece files we have, which covers
>>>>a lot of territory. But I'll let it run a ways longer forcing the 'drawing'
>>>>white move first to see if black can 'improve'.
>>>
>>>
>>>Still says 'draw'... but there is a minor problem here, in that crafty believes
>>>black is losing and so would choose a draw given the chance. And there is no
>>>way to solve this.
>>>
>>>What I might propose is that we simply play this out... I'll run crafty on the
>>>white side, you play the black side. And let's see if it is winnable against
>>>the database 'monster'. I'd suggest we start after Bh3 gxh3 (assuming gxh3 is
>>>the best move for now, since Crafty says that leads to a tablebase draw).
>>>
>>>It alternates between Kf5 and f5 as black's next move, but I'll leave that to
>>>you to choose if you want to try this. Seems like an interesting thing to do
>>>of course. I'd love to be able to write that his Bh3 was no more than a draw
>>>after his occasional comments about 'no computer will ever solve this position'
>>>only to have one find the right move in minutes. :)
>>>
>>>I have gone thru 21 plies with black's second move and crafty still says Kf5,
>>>score=0.00
>>>
>>>Bob
>>
>>After 1...Bh3 2.gxh3 I play 2...Kf5 and if 3.Kf2 I play Ke4 and if 4.Bxf6 I play
>>4...d4
>>
>>Uri
>
>
>That is exactly how the game continued...
>
>47. ... Bh3!!
>48. gxh3 Kf5
>49. Kf2 Ke4
>50. Bxf6 d4
>51. Be7 Kd3
>52. Bc5 Kc4
>53. Be7 Kb3
>
>and White resigned.
>
>According to Seirawan's notes in Inside Chess, Black will play 54...Kc2 and
>queen one of the pawns.
>
>So, can Crafty improve upon Topalov's play?
>
>--Peter
After the moves
47. ... Bh3!!
48. gxh3 Kf5
49. Kf2 Ke4
50. Bxf6
FEN: 8/8/5Bp1/3p/p3k2P/7P/5K/8 b
Crafty 16.5 sees a clear win for black
12-> 5.06 -0.36 1. ... a3 2. Ba1 Kf4 3. Bc3 Ke4 4.
Ke2 a2 5. Ba1 Kf4 6. Kf2 Ke4 <HT>
13 9.39 -0.08 1. ... a3 2. Ba1 a2 3. Ke2 Kf4 4. Kf2
Ke4 <HT>
13-> 11.65 -0.08 1. ... a3 2. Ba1 a2 3. Ke2 Kf4 4. Kf2
Ke4 <HT>
14 14.86 0.00 1. ... a3 2. Ba1 a2 3. Ke2 Kf4 4. Kf2
Ke4
14-> 17.81 0.00 1. ... a3 2. Ba1 a2 3. Ke2 Kf4 4. Kf2
Ke4
15 22.06 0.00 1. ... a3 2. Ba1 a2 3. Ke2 Kf4 4. Kf2
Ke4
15 39.09 ++ 1. ... d4!!
15 42.50 0.52 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Bd6 Kb3 6. h4 a3 7. Bc5
d3 8. Ke3 a2 9. Bd4 Kc4 10. Bf6 <HT>
15-> 43.67 0.52 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Bd6 Kb3 6. h4 a3 7. Bc5
d3 8. Ke3 a2 9. Bd4 Kc4 10. Bf6 <HT>
16 50.07 0.86 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Bd6 Kb3 6. Ke1 Kc2 7. h4
d3 8. Bf4 a3 <HT>
16-> 53.48 0.86 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Bd6 Kb3 6. Ke1 Kc2 7. h4
d3 8. Bf4 a3 <HT>
17 58.40 ++ 1. ... d4!!
17 1:13 5.81 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Be7 Kb3 6. Ke1 Kc2 7. Bf6
d3 8. Bc3 Kxc3 9. Kd1 a3
17-> 1:19 5.81 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Be7 Kb3 6. Ke1 Kc2 7. Bf6
d3 8. Bc3 Kxc3 9. Kd1 a3
18 1:36 5.80 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Be7 Kb3 6. Ke1 Kc2 7. Bf8
d3 8. Bb4 a3 9. Bxa3 d2+ 10. Ke2 d1=Q+
11. Ke3
18-> 1:53 5.80 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Be7 Kb3 6. Ke1 Kc2 7. Bf8
d3 8. Bb4 a3 9. Bxa3 d2+ 10. Ke2 d1=Q+
11. Ke3
19 2:41 5.80 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Be7 Kb3 6. Ke1 Kc2 7. Bf8
d3 8. Bb4 a3 9. Bxa3 d2+ 10. Kf2 d1=Q
11. Ke3
19-> 3:32 5.80 1. ... d4 2. Be7 Kd3 3. h5 gxh5 4.
Bc5 Kc4 5. Be7 Kb3 6. Ke1 Kc2 7. Bf8
d3 8. Bb4 a3 9. Bxa3 d2+ 10. Kf2 d1=Q
11. Ke3
20 8:04 6.03 1. ... d4 2. Be7 Kd3 3. Kf3 Kc2 4.
Bb4 d3 5. Ke3 a3 <HT>
20-> 9:43 6.03 1. ... d4 2. Be7 Kd3 3. Kf3 Kc2 4.
Bb4 d3 5. Ke3 a3 <HT>
I use not all of the 5-piece tablebases but some.
Crafty's problem is 50. ...a3 which is a blunder that may lead to a draw.
So Shirov is right and crafty is wrong.
Kind regards
Bernhard
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