Author: blass uri
Date: 20:08:47 03/10/99
Go up one level in this thread
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
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