Author: Michael Fuhrmann
Date: 00:37:51 03/08/02
Go up one level in this thread
On March 08, 2002 at 03:32:39, Michael Fuhrmann wrote:
>On March 07, 2002 at 22:54:00, Robert Hyatt wrote:
>
>>On March 07, 2002 at 22:00:56, Michael Fuhrmann wrote:
>>
>>>Crafty, playing without tablebases, likes the suicidal move Bxe3 in this
>>>position. A flaw in its endgame knowledge?
>>>
>>>[D] 8/8/2k3P1/8/3b4/4R3/8/n4K2 b - - 0 56
>>
>>
>>Do you have something broken? Mine finds Bxe3 at ply=1, but at ply=2 it
>>fails low to something winning for white and it changes to Kc5 and sticks
>>with it forever...
>>
>>I can't reproduce Bxe3 beyond a 1 ply search and wouldn't expect to be able
>>to do so as it is a trivial losing move that the search will pick up instantly.
>>
>>Which version?
>
>
>latest version. here's log output from analysis, which I did after crafty played
>the move in a game vs yace::
>
>
>hash table memory = 24M bytes.
>pawn hash table memory = 6M bytes.
>threshold set to 6 pawns.
>
>
>Crafty v18.13
>
>White(1): analyze
> clearing hash tables
> book moves {e4, d4, c4, f4}
> book 0.0s 7% c4! Nf6
>in yc.fen
> book moves {e4, d4, c4, f4}
> book 0.0s 33% d4! Nf6
>8/8/2k3P1/8/3b4/4R3/8/n4K2 b - - 0 56
>
> +---+---+---+---+---+---+---+---+
> 8 | | | | | | | | |
> +---+---+---+---+---+---+---+---+
> 7 | | | | | | | | |
> +---+---+---+---+---+---+---+---+
> 6 | | | *K| | | | P | |
> +---+---+---+---+---+---+---+---+
> 5 | | | | | | | | |
> +---+---+---+---+---+---+---+---+
> 4 | | | | *B| | | | |
> +---+---+---+---+---+---+---+---+
> 3 | | | | | R | | | |
> +---+---+---+---+---+---+---+---+
> 2 | | | | | | | | |
> +---+---+---+---+---+---+---+---+
> 1 | *N| | | | | K | | |
> +---+---+---+---+---+---+---+---+
> a b c d e f g h
>
>end-game phase
> clearing hash tables
> time surplus 0.00 time limit 30.00 (3:30)
> nss depth time score variation (1)
> 7 0.41 -- 1. ... Nc2
> 7 0.51 5.14 1. ... Nc2 2. Re4 Bg7 3. Rc4+ Kd5 4.
> Rxc2 Ke4 5. Kf2
> 7 0.76 3.95 1. ... Kb7 2. g7 Bxg7 3. Re7+ Kc6 4.
> Rxg7 Kd6 5. Kf2 Nc2
> 7 0.86 3.50 1. ... Kb5 2. Re7 Bc5 3. g7 Bxe7 4.
> g8=Q Kc5 5. Ke2
> 7 0.90 3.30 1. ... Kc5 2. Re7 Kd6 3. g7 Kxe7 4.
> g8=Q Bb2 5. Kf2
> 7-> 0.97 3.30 1. ... Kc5 2. Re7 Kd6 3. g7 Kxe7 4.
> g8=Q Bb2 5. Kf2
> 8 1.07 3.35 1. ... Kc5 2. Re7 Kd6 3. g7 Kxe7 4.
> g8=Q Bb2 5. Qh7+ Kd6 6. Kf2
> 8-> 1.38 3.35 1. ... Kc5 2. Re7 Kd6 3. g7 Kxe7 4.
> g8=Q Bb2 5. Qh7+ Kd6 6. Kf2
> 9 1.47 3.35 1. ... Kc5 2. Re7 Kd6 3. g7 Kxe7 4.
> g8=Q Bb2 5. Qh7+ Kd6 6. Kf2 Bc3
> 9-> 1.86 3.35 1. ... Kc5 2. Re7 Kd6 3. g7 Kxe7 4.
> g8=Q Bb2 5. Qh7+ Kd6 6. Kf2 Bc3
> 10 2.29 -- 1. ... Kc5
> 10 5.43 3.80 1. ... Kc5 2. Re7 Kd6 3. Rh7 Ke6 4.
> Rb7 Nc2 5. g7 Bxg7 6. Rxg7 Nb4
> 10 7.18 3.55 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kd6 4.
> Qd8+ Ke5 5. Ke2 Ke4 6. Qc8 Kd5 7. Kd3
> 10-> 7.79 3.55 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kd6 4.
> Qd8+ Ke5 5. Ke2 Ke4 6. Qc8 Kd5 7. Kd3
> 11 8.27 3.65 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kd6 4.
> Ke2 Bf6 5. Kd3 Be5 6. Qb8+ Kd5 7. Qd8+
> Kc5 8. Ke4
> 11-> 10.19 3.65 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kd6 4.
> Ke2 Bf6 5. Kd3 Be5 6. Qb8+ Kd5 7. Qd8+
> Kc5 8. Ke4
> 12 10.83 3.65 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kd6 4.
> Ke2 Bf6 5. Kd3 Be5 6. Qb8+ Kd5 7. Qd8+
> Kc5 8. Ke4 Bb2
> 12-> 13.32 3.65 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kd6 4.
> Ke2 Bf6 5. Kd3 Be5 6. Qb8+ Kd5 7. Qd8+
> Kc5 8. Ke4 Bb2
> 13 16.13 3.65 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kc5 4.
> Qd8 Kc4 5. Ke2 Be5 6. Qd3+ Kc5 7. Ke3
> Bb2 8. Qf5+ Kc4 9. Ke4
> 13-> 20.40 3.65 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kc5 4.
> Qd8 Kc4 5. Ke2 Be5 6. Qd3+ Kc5 7. Ke3
> Bb2 8. Qf5+ Kc4 9. Ke4
> 14 31.98 -- 1. ... Bxe3
> 14 37.96 4.08 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kc5 4.
> Ke2 Kb4 5. Kd3 Nb3 6. Qc4+ Ka3 7. Kc2
> Na1+ 8. Kb1 Nb3 9. Qb5 Nd2+ 10. Kc2
> 14-> 1:57 4.08 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kc5 4.
> Ke2 Kb4 5. Kd3 Nb3 6. Qc4+ Ka3 7. Kc2
> Na1+ 8. Kb1 Nb3 9. Qb5 Nd2+ 10. Kc2
> 15 2:08 4.08 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kc5 4.
> Ke2 Kb4 5. Kd3 Nb3 6. Qc4+ Ka3 7. Kc2
> Na1+ 8. Kb1 Nb3 9. Qb5 Nd2+ 10. Kc2
> Nf3
> 15-> 2:35 4.08 1. ... Bxe3 2. g7 Bd4 3. g8=Q Kc5 4.
> Ke2 Kb4 5. Kd3 Nb3 6. Qc4+ Ka3 7. Kc2
> Na1+ 8. Kb1 Nb3 9. Qb5 Nd2+ 10. Kc2
> Nf3
> 16 3:43 -- 1. ... Bxe3
>Black(0): quit
>execution complete.
and here's portion of log from the actual game:
White(56): time 32069
time remaining: 5:20 (crafty).
White(56): otim 41106
time remaining: 6:51 (opponent).
White(56): g6
time used: 9.78
time surplus 0.00 time limit 12.82 (1:29)
nss depth time score variation (1)
11 0.93 3.65 56. ... Bxe3 57. g7 Bd4 58. g8=Q Kd6
59. Ke2 Kc5 60. Kd3 Be5 61. Ke4 Bb2
62. Qb8
11-> 4.39 3.65 56. ... Bxe3 57. g7 Bd4 58. g8=Q Kd6
59. Ke2 Kc5 60. Kd3 Be5 61. Ke4 Bb2
62. Qb8
12 5.71 3.65 56. ... Bxe3 57. g7 Bd4 58. g8=Q Kd6
59. Ke2 Be5 60. Qd8+ Ke6 61. Kd3 Bf6
62. Qc8+ Kd5 63. Qa8+ Kd6 64. Ke4
12-> 9.27 3.65 56. ... Bxe3 57. g7 Bd4 58. g8=Q Kd6
59. Ke2 Be5 60. Qd8+ Ke6 61. Kd3 Bf6
62. Qc8+ Kd5 63. Qa8+ Kd6 64. Ke4
13 11.17 3.65 56. ... Bxe3 57. g7 Bd4 58. g8=Q Kd6
59. Ke2 Be5 60. Qd8+ Ke6 61. Kd3 Bf6
62. Qc8+ Kd5 63. Qd7+ Ke5 64. Qb5+
Kf4 65. Qa5
time=14.25 cpu=98% mat=0 n=4209967 fh=88% nps=295k
ext-> chk=236770 cap=15 pp=9435 1rep=1401 mate=299
predicted=13 nodes=4209967 evals=0
endgame tablebase-> probes done=0 successful=0
hashing-> trans/ref=62% pawn=99% used=48%
Black(56): Bxe3
time used: 14.25
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Last modified: Thu, 15 Apr 21 08:11:13 -0700
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