Author: Simon Finn
Date: 02:10:13 10/20/01
Go up one level in this thread
On October 18, 2001 at 23:34:45, Slater Wold wrote: >On October 18, 2001 at 22:55:02, Dann Corbit wrote: > >>On October 18, 2001 at 21:01:46, Slater Wold wrote: >> >>>On October 18, 2001 at 09:14:43, José Antônio Fabiano Mendes wrote: >>> >>>> L.D.Evans-Haik,London 1978 [unusual and difficult position] >>>> [D]8/p2P3P/k7/8/8/2q5/6PK/1Q6 b >>>> "Surprisingly Black can deliver perpetual check or force stalemate." I'm not sure if this is literally true - I think White can force a drawn KQPKQP endgame instead. >>>> Source:"Tactical Chess Endings",by GM John Nunn,page 35 >>> >>>Talk about a bummer.............. >>> >>>EPD Kit revision date: 1996.04.21 >>>found computer opening book file [./bookc.bin]. >>>max threads set to 2 >>>hash table memory = 768M bytes. >>>pawn hash table memory = 40M bytes. >>>EGTB cache memory = 32M bytes. >>>6 piece tablebase files found >>>26330kb of RAM used for TB indices and decompression tables >>>choose from 2 best moves. >>> >>> >>>Crafty v18.12 (2 cpus) >>> >>>White(1): st 3600 >>>search time set to 3600.00. >>>White(1): epdpfga drawtest.epd drawtest.out >>>PFGA: EPD record: 1 >>>end-game phase >>> clearing hash tables >>> time surplus 0.00 time limit 60:00 (60:00) >>> nss depth time score variation (1) >>>starting thread 1 >>> 7 0.14 6.02 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kg5 Qd2+ 6. Kh5 Qd4 >>> 7. Qg6+ Kb7 8. g4 >>> 7-> 0.16 6.02 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kg5 Qd2+ 6. Kh5 Qd4 >>> 7. Qg6+ Kb7 8. g4 >>> 8 0.29 5.92 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kg5 Qe3+ 6. Kf6 Qd4+ >>> 7. Ke6 Qc4+ 8. Ke5 Qc7+ 9. Ke6 Qd8 >>> 8-> 0.33 5.92 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kg5 Qe3+ 6. Kf6 Qd4+ >>> 7. Ke6 Qc4+ 8. Ke5 Qc7+ 9. Ke6 Qd8 >>> 9 0.63 5.92 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kg5 Qe3+ 6. Kf6 Qd4+ >>> 7. Ke6 Qc4+ 8. Ke5 Qc3+ 9. Kd5 Qa5+ >>> 10. Ke6 Qd8 >>> 9-> 0.72 5.92 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kg5 Qe3+ 6. Kf6 Qd4+ >>> 7. Ke6 Qc4+ 8. Ke5 Qc3+ 9. Kd5 Qa5+ >>> 10. Ke6 Qd8 >>> 10 1.24 5.82 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kf3 Qc3+ 6. Kf4 Qd2+ >>> 7. Ke5 Qc3+ 8. Ke6 Qc4+ 9. Ke5 Qc5+ >>> 10. Kf4 Qd6+ 11. Kf3 Qa3+ <HT> >>> 10-> 1.33 5.82 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kf3 Qc3+ 6. Kf4 Qd2+ >>> 7. Ke5 Qc3+ 8. Ke6 Qc4+ 9. Ke5 Qc5+ >>> 10. Kf4 Qd6+ 11. Kf3 Qa3+ <HT> >>> 11 2.30 5.82 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kf3 Qc3+ 6. Kf4 Qd2+ >>> 7. Ke5 Qc3+ 8. Ke6 Qc4+ <HT> >>> 11-> 2.71 5.82 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kf3 Qc3+ 6. Kf4 Qd2+ >>> 7. Ke5 Qc3+ 8. Ke6 Qc4+ <HT> >>> 12 5.02 5.82 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kf3 Qc3+ 6. Kf4 Qd2+ >>> 7. Ke5 Qc3+ 8. Kd5 Qd2+ 9. Ke6 Qe3+ >>> 10. Kf6 Qd4+ <HT> >>> 12-> 5.50 5.82 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kg4 Qd4+ 5. Kf3 Qc3+ 6. Kf4 Qd2+ >>> 7. Ke5 Qc3+ 8. Kd5 Qd2+ 9. Ke6 Qe3+ >>> 10. Kf6 Qd4+ <HT> >>> 13 7.79 ++ 1. ... Qe5+!! >>> 13 13.49 4.22 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kh4 Qe7+ 5. Kh5 Qc5+ 6. Kh6 Qf8+ >>> 7. Kg5 Qe7+ 8. Kf4 Qd6+ 9. Ke3 Qg3+ >>> 10. Kd2 Qxg2+ 11. Ke3 Qg3+ 12. Kd4 >>> Qd6+ 13. Kc4 Qc7+ 14. Kb4 Qd8 >>> 13-> 14.55 4.22 1. ... Qe5+ 2. Kh3 Qh5+ 3. Kg3 Qe5+ >>> 4. Kh4 Qe7+ 5. Kh5 Qc5+ 6. Kh6 Qf8+ >>> 7. Kg5 Qe7+ 8. Kf4 Qd6+ 9. Ke3 Qg3+ >>> 10. Kd2 Qxg2+ 11. Ke3 Qg3+ 12. Kd4 >>> Qd6+ 13. Kc4 Qc7+ 14. Kb4 Qd8 >>> 14 25.82 ++ 1. ... Qe5+!! >>> 14 27.55 2.00 1. ... Qe5+ 2. Kh3 Qe6+ 3. g4 Qe3+ >>> 4. Kh2 Qf4+ 5. Kg2 Qxg4+ 6. Kf2 Qf4+ >>> 7. Ke2 Qg4+ 8. Ke3 Qg3+ 9. Kd4 Qd6+ >>> 10. Ke4 Qb4+ 11. Kd5 Qxb1 12. h8=Q >>> Qa2+ 13. Kc6 Qc2+ 14. Kd6 >>> 14-> 29.02 2.00 1. ... Qe5+ 2. Kh3 Qe6+ 3. g4 Qe3+ >>> 4. Kh2 Qf4+ 5. Kg2 Qxg4+ 6. Kf2 Qf4+ >>> 7. Ke2 Qg4+ 8. Ke3 Qg3+ 9. Kd4 Qd6+ >>> 10. Ke4 Qb4+ 11. Kd5 Qxb1 12. h8=Q >>> Qa2+ 13. Kc6 Qc2+ 14. Kd6 >>> 15 32.80 2.00 1. ... Qe5+ 2. Kh3 Qe6+ 3. g4 Qe3+ >>> 4. Kh2 Qf4+ 5. Kg2 Qxg4+ 6. Kf2 Qf4+ >>> 7. Ke2 Qg4+ 8. Ke3 Qg3+ 9. Kd4 Qd6+ >>> 10. Ke4 Qb4+ 11. Kd5 Qxb1 12. h8=Q >>> Qa2+ 13. Kd6 Qd2+ 14. Kc7 Qc2+ <HT> >>> 15-> 34.79 2.00 1. ... Qe5+ 2. Kh3 Qe6+ 3. g4 Qe3+ >>> 4. Kh2 Qf4+ 5. Kg2 Qxg4+ 6. Kf2 Qf4+ >>> 7. Ke2 Qg4+ 8. Ke3 Qg3+ 9. Kd4 Qd6+ >>> 10. Ke4 Qb4+ 11. Kd5 Qxb1 12. h8=Q >>> Qa2+ 13. Kd6 Qd2+ 14. Kc7 Qc2+ <HT> >>> 16 46.88 -- 1. ... Qe5+ >>> time=60:01 cpu=201% mat=2 n=1693306751 fh=99% nps=470k >>> ext-> chk=1363197943 cap=274706 pp=267447 1rep=117221890 mate=2380 >>> >>> predicted=0 nodes=1693306751 evals=7323296 >>> endgame tablebase-> probes done=48149 successful=4738 >>> hashing-> trans/ref=73% pawn=99% used=14% >>> SMP-> split=4869 stop=472 data=13/32 cpu=120:40 elap=60:01 >>>Black(1): >>> >>> >>>Fails low @ 46 seconds, and can't resolve it in 59 minutes. :( >> >>This looks like a bug. That position should never fail low, but always fail >>high. Why? The position is ultimately drawn, but that doesn't mean there won't be some nasty shocks on the way. >> >>Either that, or crafty may have found some strange, suicidal attack that >>succeeds. > >If I had to guess, I'd say it'll find something. I did it with 10 minutes at >first, and it did this same thing. 59 minutes to resolve a fail low _does_ seem >a tad long. Perhaps Bob can help here. I had a long look at this position yesterday. White will win if he can get his king to a1 - this allows him to interpose the queen and eventually kill the checks. To prevent this, Black has to answer Ka2 with Qa4+/Qa5+ and Kb2 with Qd4+/e5+. This requirement restricts where Black can check when the White king is on other squares too. I think (but I'm not 100% sure) that answering Ke3 with Qg3+ loses because the White king can eventually get to a1. Crafty may just have discovered this and needs to spend a lot of time finding an alternative system of defence that works. (Black should arrange things to answer Ke3 with Qc5+, for example.) Simon > >I can give it more time, if requested.
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