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Subject: Re: L.D.Evans-Haik,London 1978 (bob, please look)

Author: Slater Wold

Date: 20:34:45 10/18/01

Go up one level in this thread


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."
>>>    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.
>
>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 can give it more time, if requested.



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