Stockfish 1.7.1 displays weird mate scores

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Jouni
Posts: 3283
Joined: Wed Mar 08, 2006 8:15 pm

Stockfish 1.7.1 displays weird mate scores

Post by Jouni »

Of course nothing to do with strength but only notice.

[D]1BK5/1R4b1/2k1Np2/3p3b/2p3pq/p1rB4/n2n1p2/8 w - - 14x

1.Nd4+ Kc5 2.Ba7+ Kd6 3.Rd7+ Ke5 4.Re7+ Kf4 5.Bb8+ Kg5 6.Rxg7+ Bg6 7.Ne6+ Kh5 8.Bxg6+ Kh6 9.Bf5 f1Q 10.Rh7#
+- (#10) Depth: 16 00:00:03 7216kN

[D]5K2/8/8/8/8/4N3/1N1p4/2k5 w - - 17x

1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka1 7.Nc2+ Kb1 8.Kb3 Kc1 9.Nce3 Kb1 10.Kc4 Ka2 11.Nc2 Kb1 12.Kb3
+- (11.51) Depth: 23 00:00:01 2732kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka1 7.Nc2+ Kb1 8.Kb3 Kc1 9.Nce3 Kb1 10.Nc4 Kc1 11.Ncb2 Kb1 12.Nd3 Ka1 13.N3b2 Kb1
+- (#36) Depth: 23 00:00:01 2733kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka1 7.Nc2+ Kb1 8.Kb3 Kc1 9.Nce3 Kb1 10.Nc4 Kc1 11.Ncb2 Kb1 12.Kc4 Ka2 13.Kb4 Kb1 14.Kc3 Ka2 15.Nc4 Ka1 16.Kb4 Ka2
+- (#36) Depth: 23 00:00:01 2733kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka1 7.Nc2+ Kb1 8.Kb3 Kc1 9.Nce3 Kb1 10.Nc4 Kc1 11.Ncb2 Kb1 12.Kc3 Ka2 13.Nc4 Ka1 14.Kb4 Ka2 15.Nce3 Kb1 16.Kb3 Ka1
+- (#36) Depth: 23 00:00:01 2733kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka1 7.Nc2+ Kb1 8.Kb3 Kc1 9.Nce3 Kb1 10.Nc4 Kc1 11.Ncb2 Kb1 12.Kb4 Kc2 13.Kc4 Kb1 14.Kc3 Ka2 15.Nc4 Ka1 16.Kb4 Ka2
+- (#36) Depth: 23 00:00:01 2733kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Nc4 Ka1 8.Kb3 Kb1 9.Nce3 Ka1 10.Kc2 Ka2 11.Nc3+ Ka3 12.Kd1 Kb4 13.Ne2 Kb3 14.Ng4 Ka2 15.Ne5 Kb2 16.Nf3 Kb3
+- (6.90) Depth: 23 00:00:01 3140kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Nc3+ Kc1 11.Ne2+ Kb1 12.Nd1 Ka1 13.Nd4 Kb1 14.Nc3+ Kc1 15.Nde2#
+- (#38) Depth: 24 00:00:01 3387kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Nc3+ Kc1 11.Ne2+ Kb1 12.Nd1 Ka1 13.Ka3 Kb1 14.Kb3
+- (#38) Depth: 24 00:00:01 3387kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Nc3+ Kc1 11.Na2+ Kb1 12.Nc3+
+- (#38) Depth: 24 00:00:01 3388kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Nc4 Kc1 11.Ncb2 Kb1 12.Kc3 Ka2 13.Nc4 Ka1 14.Kb4 Ka2 15.Nce3
+- (#38) Depth: 24 00:00:01 3388kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Kb4 Ka2 11.Nc4 Ka1 12.Kc5 Kb1 13.Nce3 Kc1 14.Kb4 Kb1
+- (#39) Depth: 24 00:00:01 3388kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Kb4 Ka2 11.Ng4 Ka1 12.Ka3 Kb1 13.Kb3 Ka1 14.Nge3 Kb1
+- (#38) Depth: 24 00:00:01 3388kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Ng4 Ka1 11.Nge3 Kb1
+- (#38) Depth: 24 00:00:01 3388kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Ng4 Ka1 11.Kb4 Kb1 12.Kb3
+- (#38) Depth: 24 00:00:01 3388kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Kb3 Kb1 10.Ng4 Ka1 11.Kb4 Kb1 12.Kc4 Ka2 13.Kb4 Ka1 14.Ka3 Kb1 15.Kb3
+- (#38) Depth: 24 00:00:01 3388kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc2 Ka2 12.Nc3+ Ka3 13.Kd1 Kb4 14.Ne2 Kc5 15.Nf5 Kb4 16.Ned4 Kc4
+- (6.90) Depth: 24 00:00:02 4377kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Nc4 Kb1 12.Kb4 Ka1 13.Kc5 Kb1 14.Nce3 Ka1 15.Kb5 Kb1 16.Kc4 Ka2
+- (6.98) Depth: 25 00:00:02 5196kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Nc4 Kb1 12.Kb4 Ka1 13.Nce3 Kb1
+- (7.07) Depth: 25 00:00:02 5199kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kd4 Ka2 13.Kd5 Kb3 14.Kc5 Ka3 15.Nc4+ Ka4 16.Kb6 Kb3
+- (7.23) Depth: 25 00:00:02 5199kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kc5 Ka1 13.Kb5 Kb1 14.Kc4 Ka2 15.Nc2 Kb1 16.Kb3 Kc1
+- (7.55) Depth: 25 00:00:02 5200kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kc5 Ka1 13.Kb5 Kb1 14.Kb4 Ka2 15.Nc2 Kb1 16.Kb3 Kc1
+- (8.20) Depth: 25 00:00:02 5201kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kc5 Ka1 13.Kb5 Kb1 14.Kc4 Ka2 15.Nc2 Kb1 16.Kb3 Kc1
+- (9.49) Depth: 25 00:00:02 5201kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kc5 Ka1 13.Kb5 Kb1 14.Kb4 Ka2 15.Nc2 Kb1 16.Kb3 Kc1
+- (12.08) Depth: 25 00:00:02 5201kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kc5 Ka1 13.Kb5 Kb1 14.Kc4 Ka2 15.Nc2 Kb1 16.Kb3 Kc1
+- (#38) Depth: 25 00:00:02 5201kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kb4 Ka2 13.Nc2 Kb1 14.Kb3 Kc1 15.Nce3 Kb1 16.Nc3+ Kc1
+- (#38) Depth: 25 00:00:02 5201kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kb4 Ka2 13.Nf1 Kb1 14.Kb3 Ka1 15.Nfe3 Kb1 16.Nc3+ Kc1
+- (#45) Depth: 25 00:00:02 5202kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Kc1 5.Kd4 Kb1 6.Kc3 Ka2 7.Kb4 Kb1 8.Ka3 Kc1 9.Ka4 Kb1 10.Kb3 Ka1 11.Kc4 Kb1 12.Kb4 Ka2 13.Nc2 Kb1 14.Kb3 Kc1 15.Nce3 Kb1 16.Nc3+ Kc1
+- (#38) Depth: 25 00:00:02 5202kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kc5 Ka3 7.Nc4+ Ka4 8.Kb6 Kb3 9.Kb5 Kc2 10.Nce3+ Kb3 11.Kc5
+- (6.82) Depth: 25 00:00:02 6677kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Kc3 Ka2 12.Nc4 Ka1 13.Kc2 Ka2 14.Nc3+ Ka1 15.Kd1
+- (7.83) Depth: 25 00:00:03 8836kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kb3 Kb1 13.Nce3 Ka1 14.Kc4 Kb1 15.Kb5 Ka1 16.Kc4
+- (#36) Depth: 26 00:00:03 9046kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kb5 Kb1 13.Nce3 Ka1 14.Kc4 Kb1 15.Kb5
+- (#40) Depth: 26 00:00:03 9046kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kb5 Kb1 13.Nce3 Ka1 14.Ng4 Kb1 15.Nge3
+- (#40) Depth: 26 00:00:03 9046kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kb5 Kb1 13.Nce3 Ka1 14.Kc4 Kb1 15.Kb5
+- (#40) Depth: 26 00:00:03 9046kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kb5 Kb1 13.Nce3 Ka1 14.Ng4 Kb1 15.Nge3
+- (#40) Depth: 26 00:00:03 9046kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kb5 Kb1 13.Nce3 Ka1 14.Kc4 Kb1 15.Kb5
+- (#40) Depth: 26 00:00:03 9046kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kb5 Kb1 13.Nce3 Ka1 14.Ng4 Kb1 15.Nge3
+- (#40) Depth: 26 00:00:03 9046kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Ke6 Kb1 4.Kd5 Ka2 5.Kc6 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kb5 Kb1 13.Nce3 Ka1 14.Kc4 Kb1 15.Kb5
+- (#40) Depth: 26 00:00:03 9046kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nc4+ Kb3 7.Ncb2 Ka3 8.Kc4 Ka2 9.Kb4 Kb1 10.Nc4 Ka1 11.Kc5 Kb1 12.Kd4 Kc1 13.Nce3 Kb1 14.Kc3 Ka2 15.Nc4 Ka1 16.Kc2 Ka2
+- (7.83) Depth: 26 00:00:04 10868kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nc4+ Kb3 7.Ncb2 Ka3 8.Kc4 Ka2 9.Kb4 Kb1 10.Nc4 Ka1 11.Kc5 Kb1 12.Kd4 Kc1 13.Nce3 Kb1 14.Kc4 Ka2 15.Nc2 Kb1 16.Kb3 Kc1
+- (#47) Depth: 27 00:00:04 11245kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nc4+ Kb3 7.Ncb2 Ka3 8.Kc4 Ka2 9.Kb4 Kb1 10.Nc4 Ka1 11.Kb5 Kb1 12.Nce3 Ka1 13.Kb4 Ka2 14.Nc2 Kb1 15.Kb3 Kc1 16.Nce3 Kb1
+- (#39) Depth: 27 00:00:04 11245kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nc4+ Kb3 7.Ncb2 Ka3 8.Kc4 Ka2 9.Kb4 Kb1 10.Nc4 Ka1 11.Nce3 Ka2 12.Nc2 Kb1 13.Kb3 Kc1 14.Nce3 Kb1 15.Nc3+ Kc1 16.Na2+ Kb1
+- (#36) Depth: 27 00:00:04 11245kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nd5 Ka2 7.Kb4 Kb1 8.N5e3 Ka2 9.Nc2 Kb1 10.Kb3 Kc1 11.Nce3 Kb1 12.Nc3+ Kc1 13.Na2+ Kb1 14.Nd1 Ka1 15.Nb4 Kb1 16.Nc3+ Kc1
+- (#41) Depth: 27 00:00:04 11283kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nd5 Ka2 7.Kb4 Kb1 8.N5e3 Ka2 9.Nc2 Kb1 10.Kb3 Kc1 11.Nce3 Kb1 12.Kc4 Ka2 13.Nc2 Kb1 14.Kb3
+- (#41) Depth: 27 00:00:04 11283kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nd5 Ka2 7.Kb4 Kb1 8.N5e3 Ka2 9.Ka4 Kb1 10.Kb5 Ka1 11.Kc5 Kb1 12.Kb5
+- (#41) Depth: 27 00:00:04 11283kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nd5 Ka2 7.Kb4 Kb1 8.N5e3 Ka2 9.Ka4 Kb1 10.Ka5 Kc1 11.Kb6 Kb1 12.Kc7 Ka1 13.Kd6
+- (#53) Depth: 27 00:00:04 11284kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nd5 Ka2 7.Kb4 Kb1 8.Kb3 Kc1 9.N5e3 Kb1 10.Nc3+ Kc1 11.Na2+ Kb1 12.Nd1 Ka1 13.Nb4 Kb1 14.Nc3+ Kc1 15.Nba2#
+- (#41) Depth: 27 00:00:04 11285kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Nd5 Ka2 7.Kb4 Kb1 8.Kb3 Kc1 9.N5e3 Kb1 10.Nc3+ Kc1 11.Na2+ Kb1 12.Nd1 Ka1 13.Nb4 Kb1 14.Nc3+ Kc1 15.Nba2#
+- (#41) Depth: 27 00:00:04 11285kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc6 Kb3 5.Kb5 Ka3 6.Kc5 Kb3 7.Kb5
+- (7.35) Depth: 27 00:00:05 13681kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd6 Ka2 4.Kc5 Ka3 5.Nc4+ Ka4 6.Kb6 Kb3 7.Kb5 Kc2 8.Ncb2 Kb1 9.Kb4 Kc2 10.Kc5 Kb3 11.Kc6 Ka2 12.Kd7 Kb1 13.Ke6 Kc2 14.Kd6 Kc1 15.Kc6 Kb1 16.Kb5 Kc1
+- (6.86) Depth: 27 00:00:06 20289kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd7 Ka2 4.Kc6 Ka3 5.Kc5 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Ka3 Kc2 12.Ka2 Kc1 13.Kb3 Kb1 14.Nd3 Ka1 15.Nb4 Kb1 16.Nc3+ Kc1
+- (#17) Depth: 27 00:00:09 29533kN
1.Nbd1 Kb1 2.Ke7 Ka1 3.Kd7 Ka2 4.Kc6 Ka3 5.Kc5 Kb3 6.Kb5 Ka3 7.Nc4+ Kb3 8.Ncb2 Ka3 9.Kc4 Ka2 10.Kb4 Kb1 11.Nc4 Ka1 12.Kc3 Ka2 13.Kc2 Ka1 14.Nce3 Ka2 15.Nc3+ Ka3 16.Kd1 Kb4
+- (7.15) Depth: 28 00:00:10 32233kN

[D]8/8/2k5/8/3p4/Qp1p4/pp1p4/rrbK4 w - - 20x

1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Kb8 7.Qc6 Ka7 8.Qc8 Kb6 9.Qd7 Kc5 10.Qe6 Kb5 11.Qd6 Ka5 12.Qd8+ Kb5 13.Qc7 Ka6 14.Qb8 Ka5 15.Qb7 Ka4 16.Qb6
+- (#24) Depth: 33 00:00:03 14198kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Kb8 7.Qc6 Ka7 8.Qc8 Kb6 9.Qd7 Kc5 10.Qe6 Kb5 11.Qd6 Ka5 12.Qd8+ Kb5 13.Qc7 Ka6 14.Qb8 Ka5 15.Qb7 Ka4 16.Qb6
+- (#24) Depth: 33 00:00:03 14198kN
1.Qc5+ Kxc5
= (0.00) Depth: 34 00:00:03 15022kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe8+ Kc7 12.Qe6 Kd8 13.Qf7 Kc8 14.Qe7 Kb8 15.Qd7 Ka8 16.Qd5+ Ka7
+- (#31) Depth: 34 00:00:04 15746kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe8+ Kc7 12.Qe6 Kd8 13.Qf7 Kc8 14.Qe7 Kb8 15.Qd7 Ka8 16.Qd5+ Ka7
+- (#45) Depth: 34 00:00:04 15746kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe8+ Kc7 12.Qe6 Kd8 13.Qf7 Kc8 14.Qe7 Kb8 15.Qd7 Ka8 16.Qd5+ Ka7
+- (#41) Depth: 34 00:00:04 15746kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe8+ Kc7 12.Qe7+ Kc6 13.Qe6+ Kc7
+- (#38) Depth: 34 00:00:04 15747kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe7 Kb8 12.Qd8+ Kb7 13.Qd6 Ka7 14.Qd5 Kb6 15.Qe4 Ka7 16.Qe7+ Kb8
+- (#37) Depth: 34 00:00:04 15748kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe7 Kb8 12.Qd8+ Kb7 13.Qd6 Ka7 14.Qd5 Kb6 15.Qe6+ Kc7
+- (#40) Depth: 34 00:00:04 15748kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe7 Kb8 12.Qd8+ Kb7 13.Qd6 Ka7 14.Qd5 Kb6 15.Qd6+ Kb7
+- (#38) Depth: 34 00:00:04 15748kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe7 Kb8 12.Qd8+ Kb7 13.Qd6 Ka7 14.Qd5 Kb6 15.Qd7 Kc5 16.Qe6 Kb5
+- (#37) Depth: 34 00:00:04 15748kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe5+ Kc8 11.Qe7 Kb8 12.Qd8+ Kb7 13.Qd6 Ka7 14.Qd5 Kb6 15.Qd7 Kc5 16.Qe6 Kb5
+- (#37) Depth: 34 00:00:04 15748kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe7 Ka8 11.Qg7
+- (#32) Depth: 34 00:00:04 15750kN
1.Qa8+ Kd7 2.Qe4 Kd8 3.Qe6 Kc7 4.Qd5 Kc8 5.Qd6 Kb7 6.Qc5 Ka8 7.Qc8+ Ka7 8.Qc7+ Ka8 9.Qg7 Kb8 10.Qe7 Ka8 11.Qc5 Kb7 12.Qd6 Ka7 13.Qc7+
+- (#35) Depth: 34 00:00:04 15750kN
1.Qc5+ Kxc5
= (0.00) Depth: 35 00:00:04 19284kN
1.Qc5+ Kxc5
= (0.00) Depth: 36 00:00:05 20837kN
1.Qf8 Kd7 2.Qf7+ Kc8 3.Qe7 Kb8 4.Qe5+ Ka7 5.Qc7+ Ka8 6.Qg7 Kb8 7.Qe7 Ka8 8.Qc5 Kb7 9.Qd6 Ka7 10.Qa3+ Kb7 11.Qc5 Ka8 12.Qc8+ Ka7 13.Qc7+
= (0.08) Depth: 36 00:00:05 23317kN
1.Qf8 Kd7 2.Qf7+ Kc8 3.Qe7 Kb8 4.Qe5+ Ka7 5.Qc7+ Ka8 6.Qg7 Kb8 7.Qe7 Ka8 8.Qc5 Kb7 9.Qd6 Ka7 10.Qa3+ Kb7 11.Qc5 Ka8 12.Qf8+ Kb7 13.Qd6
= (0.16) Depth: 36 00:00:05 23317kN
1.Qf8 Kd7 2.Qf7+ Kc8 3.Qe7 Kb8 4.Qe5+ Ka7 5.Qc7+ Ka8 6.Qg7 Kb8 7.Qe7 Ka8 8.Qc5 Kb7 9.Qf8 Kc6 10.Qf7 Kd6 11.Qe8 Kd5 12.Qe7 Kc6 13.Qf7
² (0.32) Depth: 36 00:00:05 23317kN
1.Qf8 Kd7 2.Qf7+ Kc8 3.Qe7 Kb8 4.Qe5+ Ka7 5.Qc7+ Ka8 6.Qg7 Kb8 7.Qe7 Ka8 8.Qc5 Kb7 9.Qf8 Kc6 10.Qf7 Kd6 11.Qe8 Kd5 12.Qe7 Kc6 13.Qe6+ Kc7 14.Qe7+ Kc6
+- (#52) Depth: 36 00:00:05 23344kN
1.Qf8 Kd7 2.Qf7+ Kc8 3.Qe7 Kb8 4.Qe5+ Ka7 5.Qc7+ Ka8 6.Qg7 Kb8 7.Qe7 Ka8 8.Qc5 Kb7 9.Qf8 Kc6 10.Qf7 Kd6 11.Qe8 Kd5 12.Qe7 Kc6 13.Qe6+ Kc7 14.Qd5 Kc8 15.Qd6 Kb7 16.Qc5 Ka8
± (1.29) Depth: 36 00:00:05 23345kN
1.Qf8 Kd7 2.Qf7+ Kc8 3.Qe7 Kb8 4.Qe5+ Ka7 5.Qc7+ Ka8 6.Qg7 Kb8 7.Qe7 Ka8 8.Qc5 Kb7 9.Qf8 Kc6 10.Qf7 Kd6 11.Qe8 Kd5 12.Qe7 Kc6 13.Qe6+ Kc7 14.Qd5 Kc8 15.Qd6 Kb7 16.Qc5 Ka8
+- (2.58) Depth: 36 00:00:05 23345kN
1.Qf8 Kd7 2.Qf7+ Kc8 3.Qe7 Kb8 4.Qe5+ Ka7 5.Qc7+ Ka8 6.Qg7 Kb8 7.Qe7 Ka8 8.Qc5 Kb7 9.Qf8 Kc6 10.Qf7 Kd6 11.Qe8 Kd5 12.Qe7 Kc6 13.Qe6+ Kc7 14.Qd5 Kc8 15.Qd6 Kb7 16.Qc5 Ka8
+- (5.17) Depth: 36 00:00:05 23345kN
1.Qf8 Kd7 2.Qf7+ Kd6 3.Qe8 Kd5 4.Qe7 Kc6 5.Qe6+ Kc7 6.Qd5 Kc8 7.Qd6 Kb7 8.Qc5 Ka8 9.Qb4 Ka7 10.Qa3+ Kb7 11.Qd6 Ka7 12.Qc7+ Ka8 13.Qg7 Kb8 14.Qe7 Ka8 15.Qf7 Kb8 16.Qf8+ Kb7
+- (#58) Depth: 36 00:00:06 25904kN
1.Qf8 Kd7 2.Qf7+ Kd6 3.Qe8 Kd5 4.Qe7 Kc6 5.Qe6+ Kc7 6.Qd5 Kc8 7.Qd6 Kb7 8.Qc5 Ka8 9.Qb4 Ka7 10.Qa3+ Kb7 11.Qd6 Ka7 12.Qc7+ Ka8 13.Qg7 Kb8 14.Qe5+ Ka7 15.Qc7+
+- (#51) Depth: 36 00:00:06 25904kN
1.Qf8 Kd7 2.Qf7+ Kd6 3.Qe8 Kd5 4.Qe7 Kc6 5.Qe6+ Kc7 6.Qd5 Kc8 7.Qd6 Kb7 8.Qc5 Ka8 9.Qb4 Ka7 10.Qa3+ Kb7 11.Qd6 Ka7 12.Qc7+ Ka8 13.Qg7 Kb8 14.Qe5+ Ka7 15.Qd6 Kb7
+- (#51) Depth: 36 00:00:06 25905kN
1.Qf8 Kd7 2.Qf7+ Kd6 3.Qe8 Kd5 4.Qe7 Kc6 5.Qe6+ Kc7 6.Qd5 Kc8 7.Qd6 Kb7 8.Qc5 Ka8 9.Qb4 Ka7 10.Qa3+ Kb7 11.Qd6 Ka7 12.Qc7+ Ka8 13.Qf7 Kb8 14.Qg7 Kc8 15.Qf8+ Kd7
+- (#51) Depth: 36 00:00:06 25911kN

Jouni
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User avatar
Eelco de Groot
Posts: 4563
Joined: Sun Mar 12, 2006 2:40 am
Full name:   

Re: Stockfish 1.7.1 displays weird mate scores

Post by Eelco de Groot »

Jouni wrote:Of course nothing to do with strength but only notice.

Jouni

I'm only half sure, but I just encountered this new code in 1.7.1 line 2319 in search.cpp

Code: Select all

  // ok_to_use_TT() returns true if a transposition table score can be used at a
  // given point in search. To avoid zugzwang issues TT cutoffs at the root node
  // of a null move verification search are not allowed if the TT value was found
  // by a null search, this is implemented testing allowNullmove and TT entry type.

  bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply, bool allowNullmove) {

    Value v = value_from_tt(tte->value(), ply);

    return   (allowNullmove || !(tte->type() & VALUE_TYPE_NULL) || !ZugDetection)

          && (   tte->depth() >= depth
              || v >= Max(value_mate_in(PLY_MAX), beta)
              || v < Min&#40;value_mated_in&#40;PLY_MAX&#41;, beta&#41;)

          && (   &#40;is_lower_bound&#40;tte->type&#40;)) && v >= beta&#41;
              || &#40;is_upper_bound&#40;tte->type&#40;)) && v < beta&#41;);
  &#125;
maybe it should be:

Code: Select all

  // ok_to_use_TT&#40;) returns true if a transposition table score can be used at a
  // given point in search. To avoid zugzwang issues TT cutoffs at the root node
  // of a null move verification search are not allowed if the TT value was found
  // by a null search, this is implemented testing allowNullmove and TT entry type.

  bool ok_to_use_TT&#40;const TTEntry* tte, Depth depth, Value beta, int ply, bool allowNullmove&#41; &#123;

    Value v = value_from_tt&#40;tte->value&#40;), ply&#41;;

    return   (&#40;allowNullmove || !&#40;tte->type&#40;) & VALUE_TYPE_NULL&#41; || !ZugDetection&#41;

          && (   tte->depth&#40;) >= depth
              || v >= Max&#40;value_mate_in&#40;PLY_MAX&#41;, beta&#41;
              || v < Min&#40;value_mated_in&#40;PLY_MAX&#41;, beta&#41;)

          && (   &#40;is_lower_bound&#40;tte->type&#40;)) && v >= beta&#41;
              || &#40;is_upper_bound&#40;tte->type&#40;)) && v < beta&#41;));
  &#125;
Extra () around the Boolean.

I could be wrong but it looks a bit suspicious and it also involves the matescores, could it be correct, that only the first part of this boolean is returned at the moment?
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan
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zamar
Posts: 613
Joined: Sun Jan 18, 2009 7:03 am

Re: Stockfish 1.7.1 displays weird mate scores

Post by zamar »

Thanks for reporting the issue, Jouni!

I'll take a long look at this tonight.

This _could_ also be sth null move related.
Joona Kiiski
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BBauer
Posts: 658
Joined: Wed Mar 08, 2006 8:58 pm

Re: Stockfish 1.7.1 displays weird mate scores

Post by BBauer »

Thank you for pointing out this.
With your code change, "()" several positions are solved much faster.
Still I wonder why stockfish cannot solve this one.
[D] 8/3Pb1p1/8/3P2P1/5P2/7k/4K3/8 w - - bm Kd3; id "E_E_T 007 - B vs L";
kind regards
Bernhard
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Sven
Posts: 4052
Joined: Thu May 15, 2008 9:57 pm
Location: Berlin, Germany
Full name: Sven Schüle

Re: Stockfish 1.7.1 displays weird mate scores

Post by Sven »

Eelco de Groot wrote:I'm only half sure, but I just encountered this new code in 1.7.1 line 2319 in search.cpp
[...]
Extra () around the Boolean.

I could be wrong but it looks a bit suspicious and it also involves the matescores, could it be correct, that only the first part of this boolean is returned at the moment?
No, both versions are equivalent, it is like writing either "return a && b && c;" or "return (a && b && c);". The "return" statement does not require parentheses around the expression that follows, so they are optional. And "return a" itself is also not an expression because "return" is not an operator, so "return a && b && c;" is *not* evaluated like this (wrong code): "(return a) && b && c;".

If adding these parentheses changes behaviour then I would believe that there is something else being changed, too.

Sven
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zullil
Posts: 6442
Joined: Tue Jan 09, 2007 12:31 am
Location: PA USA
Full name: Louis Zulli

Re: Stockfish 1.7.1 displays weird mate scores

Post by zullil »

BBauer wrote:Thank you for pointing out this.
With your code change, "()" several positions are solved much faster.
Still I wonder why stockfish cannot solve this one.
[D]8/3Pb1p1/8/3P2P1/5P2/7k/4K3/8 w - - bm Kd3; id "E_E_T 007 - B vs L";
kind regards
Bernhard
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royb
Posts: 536
Joined: Thu Mar 09, 2006 12:53 am

Re: Stockfish 1.7.1 displays weird mate scores

Post by royb »

zamar wrote:Thanks for reporting the issue, Jouni!

I'll take a long look at this tonight.

This _could_ also be sth null move related.
This behavior is not new. It was in Stockfish-1.6.3 also and I reported it previously here on CCC (I'm in a hurry and cannot stop to find the posting to quote here).

Roy
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Sven
Posts: 4052
Joined: Thu May 15, 2008 9:57 pm
Location: Berlin, Germany
Full name: Sven Schüle

Re: Stockfish 1.7.1 displays weird mate scores

Post by Sven »

royb wrote:
zamar wrote:Thanks for reporting the issue, Jouni!

I'll take a long look at this tonight.

This _could_ also be sth null move related.
This behavior is not new. It was in Stockfish-1.6.3 also and I reported it previously here on CCC (I'm in a hurry and cannot stop to find the posting to quote here).
Maybe it is this thread?

Sven
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Vinvin
Posts: 5228
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: Stockfish 1.7.1 displays weird mate scores

Post by Vinvin »

You should really integrate the Stockfish team ! ;-)
Eelco de Groot wrote:
Jouni wrote:Of course nothing to do with strength but only notice.

Jouni

I'm only half sure, but I just encountered this new code in 1.7.1 line 2319 in search.cpp
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Jouni
Posts: 3283
Joined: Wed Mar 08, 2006 8:15 pm

Re: Stockfish 1.7.1 displays weird mate scores

Post by Jouni »

Note,that I tested with zuzwang detection ON. I see, that PLY_MAX = 100
so how is +- (#52) explained? (Probably 1.6 has same behaviour).

Jouni
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