Author: Robert Hyatt
Date: 06:28:00 12/12/03
Go up one level in this thread
On December 12, 2003 at 03:36:47, Omid David Tabibi wrote:
>
>I had similar problems in Falcon. I fixed the problem by storing the checkmate
>score as a bound only. Not an efficient solution of course, but haven't
>encountered any such bugs ever since.
There is no need to cripple the search by not storing mate scores at all.
Adjusting mate scores to not have such problems is very simple, as the
following output shows:
depth time score variation (1)
8 0.12 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8
8-> 0.12 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8
9 0.22 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8 Kb2
9-> 0.22 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8 Kb2
10 0.39 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8 Kb2 6. Qf8
10-> 0.39 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8 Kb2 6. Qf8
11 0.76 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8 Kb2 6. Qf8 Ka1
11-> 0.76 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8 Kb2 6. Qf8 Ka1
12 1.34 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8 Kb2 6. Qf8 Ka1 7. Kf6
12-> 1.34 10.19 1. ... Kb6 2. Qg8 Ka5 3. Qf8 Ka4 4.
Qh8 Ka3 5. Qg8 Kb2 6. Qf8 Ka1 7. Kf6
13 1.87 -- 1. ... Kb6
13 2.75 Mat09 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qd5 Ka7 7. Kc6
Kb8 8. Qd8+ <HT>
13-> 2.83 Mat09 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qd5 Ka7 7. Kc6
Kb8 8. Qd8+ <HT>
14 3.63 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
14-> 3.64 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
15 4.87 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
15-> 5.08 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
16 6.77 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
16-> 7.10 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
17 9.22 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
17-> 9.79 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
18 12.45 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
18-> 13.21 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
19 15.82 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
19-> 16.49 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
20 19.52 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
20-> 20.40 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
21 23.41 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
21-> 24.31 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
22 27.33 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
22-> 28.67 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
23 31.75 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
23-> 32.87 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
24 36.13 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
24-> 37.41 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
25 40.49 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
25-> 41.71 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
26 44.83 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
26-> 46.10 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
27 49.29 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
27-> 50.60 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
28 53.73 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
28-> 55.01 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
29 58.11 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
29-> 59.60 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
30 1:02 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
30-> 1:04 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
31 1:07 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
31-> 1:08 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
32 1:11 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
32-> 1:13 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
33 1:16 Mat08 1. ... Kb6 2. Qh5 Ka6 3. Kf6 Kb6 4.
Ke6 Ka6 5. Kd6 Kb6 6. Qc5+ Kb7 7. Qb5+
Ka7 8. Kc7 Ka8 9. Qb8#
<etc>
Shredder has a _serious_ bug in hashing somewhere.
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