Mario Matous study from 1975 solved by Stockfish

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bnst
Posts: 87
Joined: Tue Sep 11, 2007 12:16 pm

Mario Matous study from 1975 solved by Stockfish

Post by bnst »

The famous study which many have said never would be solved by computers is solved by Stockfish 180613:
Run in a single thread with 6-man Syzygy tables on I7-5820K with 4GB hash tables.
FEN: n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - 0 1

Stockfish_180613:
8/11 00:00 5 922 394 800 +0,36 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Qxa5 Kg7 Qc3+ Kg8
9/16 00:00 12 265 557 500 +0,51 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Qg6+ Kf4 Kxh7 Qxa5 Qd6+ Ke3
10/21 00:00 31 102 971 937 +0,37 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Bxa5 Qe5+ Kg4 Kg7 Qd8 Kh7 Qd2
11/22 00:00 68 854 1 405 183 +0,72 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Qe3+ Kf5 Qf2+ Ke5 Qe3+ Kd6 Qe6+ Kc5 Qe5+ Kb6 Kxh7 Qh1+ Kg8 Qg1+ Kh7
12/29 00:00 178 291 1 800 919 +0,35 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Qe3+ Kf5 Kxh7 Bxa5 Qg3 Bd8 Qf2+ Ke5 Qe3+ Kd6 Qe6+ Kc5 Qe3+ Kb4 Qe6 Ka3 Qe3+ Ka2
13/32 00:00 283 555 1 890 366 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Qe3+ Kf6
14/26 00:00 375 195 1 933 994 +0,09 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Kg2 Qg6+ Bg3 Qc2+ Kh3 a2 Kh4 Qb1
15/31 00:00 476 323 1 968 276 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 Qd1+ Kg2 Qc2+ Bf2 Qg6+ Bg3 Qc2+
16/25 00:00 506 755 1 971 809 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 Qd1+ Kg2 Qc2+ Bf2 Qg6+ Bg3 Qc2+
17/25 00:00 544 014 1 985 452 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 Qd1+ Kg2 Qc2+ Bf2 Qg6+ Bg3 Qc2+
18/25 00:00 656 549 1 995 589 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 Qd1+ Kg2 Qc2+ Bf2 Qg6+ Bg3 Qc2+
19/25 00:00 722 959 1 997 124 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 Qd1+ Kg2 Qc2+ Bf2 Qg6+ Bg3 Qc2+
20/25 00:00 882 343 2 009 892 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 Qd1+ Kg2 Qc2+ Bf2 Qg6+ Bg3 Qc2+
21/25 00:00 996 929 2 009 937 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 Qd1+ Kg2 Qc2+ Bf2 Qg6+ Bg3 Qc2+
22/25 00:00 1 186 186 2 024 208 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 Qd1+ Kg2 Qc2+ Bf2 Qg6+ Bg3 Qc2+
23/37 00:00 1 558 571 2 058 878 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
24/20 00:00 1 811 506 2 072 661 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
25/20 00:01 2 242 190 2 101 396 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
26/20 00:01 3 005 516 2 112 098 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
27/20 00:01 3 444 479 2 102 856 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
28/20 00:01 4 018 535 2 091 897 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
29/20 00:02 4 884 997 2 111 974 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
30/20 00:02 5 844 197 2 119 766 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
31/20 00:03 7 378 602 2 136 248 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
32/20 00:04 8 960 505 2 145 714 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
33/20 00:05 11 185 092 2 151 392 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
34/20 00:06 14 011 908 2 165 004 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
35/20 00:07 16 410 806 2 178 521 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
36/20 00:08 19 300 055 2 188 462 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
37/20 00:10 23 357 062 2 212 052 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
38/20 00:12 27 751 045 2 227 389 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
39/20 00:15 34 411 718 2 239 762 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
40/20 00:17 39 838 389 2 246 948 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
41/20 00:21 49 018 030 2 261 292 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
42/20 00:25 57 021 569 2 266 988 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
43/20 00:30 68 535 595 2 268 789 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
44/20 00:36 81 926 437 2 275 039 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
45/20 00:44 100 024 270 2 270 595 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
46/20 00:52 117 471 466 2 253 822 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
47/20 00:59 134 517 690 2 257 690 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
48/20 01:07 152 779 085 2 247 941 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
49/20 01:15 169 446 437 2 252 468 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
50/20 01:25 192 165 277 2 245 760 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
51/20 01:37 220 086 774 2 248 490 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
52/20 01:55 261 591 140 2 256 399 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
53/20 02:10 293 496 294 2 253 347 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
54/20 02:47 379 324 440 2 258 555 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
55/20 03:04 418 417 455 2 264 335 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
56/20 03:26 467 393 608 2 262 837 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
57/20 03:52 527 249 195 2 265 098 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
58/20 04:27 607 174 059 2 268 757 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
59/20 05:54 806 740 311 2 277 486 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
60/20 06:57 952 223 553 2 281 299 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
61/20 08:31 1 164 655 066 2 276 183 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
62/24+ 09:18 1 270 342 236 2 275 257 +0,07 Qc8
62/25+ 09:18 1 271 404 216 2 275 427 +0,15 Qc8
62/25+ 09:19 1 272 029 193 2 275 483 +0,26 Qc8
62/25+ 09:19 1 272 961 710 2 275 584 +0,42 Qc8
62/25+ 09:19 1 273 787 019 2 275 729 +0,63 Qc8
62/25+ 09:19 1 274 389 693 2 275 764 +0,92 Qc8
62/25+ 09:20 1 274 646 182 2 275 775 +1,31 Qc8
62/25+ 09:20 1 275 027 619 2 275 705 +1,81 Qc8
62/25+ 09:20 1 275 400 811 2 275 753 +2,45 Qc8
62/25+ 09:20 1 275 592 765 2 275 763 +3,28 Qc8
62/25+ 09:20 1 275 985 964 2 275 795 +4,33 Qc8
62/25+ 09:20 1 276 169 054 2 275 638 +5,66 Qc8
62/25+ 09:20 1 276 364 533 2 275 654 +7,35 Qc8
62/25+ 09:21 1 276 781 863 2 275 802 +9,48 Qc8
62/25+ 09:21 1 277 531 373 2 276 087 +12,16 Qc8
62/25+ 09:21 1 277 998 658 2 276 084 +15,52 Qc8
62/25+ 09:21 1 278 063 069 2 276 093 +19,75 Qc8
62/25+ 09:21 1 278 120 084 2 276 073 +25,06 Qc8
62/25+ 09:21 1 278 130 896 2 276 072 +132,62 Qc8
62/26 09:28 1 294 970 729 2 277 592 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Nb5 Ke6+ Nc3 Bxc3+ Qxc3 f8Q+
63/26 09:31 1 303 187 469 2 278 937 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Nb5 Ke6+ Nc3 Bxc3+ Qxc3 f8Q+
64/26 09:36 1 315 532 020 2 280 536 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Nb5 Ke6+ Nc3 Bxc3+ Qxc3 f8Q+

Best regards
anst
peter
Posts: 3236
Joined: Sat Feb 16, 2008 7:38 am
Full name: Peter Martan

Re: Mario Matous study from 1975 solved by Stockfish

Post by peter »

bnst wrote: Thu Jun 28, 2018 10:44 am The famous study which many have said never would be solved by computers is solved by Stockfish 180613:
Run in a single thread with 6-man Syzygy tables on I7-5820K with 4GB hash tables.
FEN: n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - 0 1

Stockfish_180613:
...
61/20 08:31 1 164 655 066 2 276 183 0,00 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Kf4 a4 Bh4 Qd6+ Kf3 a3 Qe4+ Kg7 Qc4 a2 Qxa2
62/24+ 09:18 1 270 342 236 2 275 257 +0,07 Qc8
...
62/25+ 09:21 1 278 120 084 2 276 073 +25,06 Qc8
62/25+ 09:21 1 278 130 896 2 276 072 +132,62 Qc8
62/26 09:28 1 294 970 729 2 277 592 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Nb5 Ke6+ Nc3 Bxc3+ Qxc3 f8Q+
...
64/26 09:36 1 315 532 020 2 280 536 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Nb5 Ke6+ Nc3 Bxc3+ Qxc3 f8Q+
Good found, thanks!

n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - 0 1

Analysis by MateFinder 280618 64:

1.Qc8 Kg8 2.gxh7+ Kh8 3.Qxa8 Qe6+ 4.Kg5 Qe3+ 5.Kf5
+/= (0.53) Depth: 7/11 00:00:01 34kN, tb=157
...
1.Qc8 Kg8 2.gxh7+ Kh8 3.Qxa8 Qe6+ 4.Kg5 Kxh7 5.Kf4 Qc4+ 6.Ke3 Qc3+ 7.Kf2 Qd2+ 8.Kf1 Qc1+ 9.Kg2 Qd2+
= (0.00) Depth: 27/19 00:00:03 44128kN, tb=877817
1.Qc8
+- (5.38 ++) Depth: 28/24 00:00:04 69378kN, tb=1499420
...
1.Qc8
+- (132.34 ++) Depth: 28/24 00:00:06 101MN, tb=2090421
1.Qc8 Kg8 2.Bc7 Qxc8 3.gxf7+ Kh8 4.Be5 Qc5 5.Bb2 Nc7 6.Ba1 a4 7.Bb2 a3 8.Ba1 a2 9.Bb2 a1Q 10.Bxa1 Nb5 11.Ke6+ Nc3 12.Bxc3+ Qxc3 13.f8Q#
+- (#13) Depth: 28/26 00:00:06 103MN, tb=2145974
...
1.Qc8 Kg8 2.Bc7 Qxc8 3.gxf7+ Kh8 4.Be5 Qc5 5.Bb2 Nc7 6.Ba1 a4 7.Bb2 a3 8.Ba1 a2 9.Bb2 a1Q 10.Bxa1 Nb5 11.Ke6+ Nc3 12.Bxc3+ Qxc3 13.f8Q#
+- (#13) Depth: 37/26 00:00:11 224MN, tb=4701292

24 threads, full Syzygys.

Without tbs slightly above 2 minutes, depth 44 for #13- output.
Peter.
Andrew
Posts: 231
Joined: Thu Mar 09, 2006 12:51 am
Location: Australia

Re: Mario Matous study from 1975 solved by Stockfish

Post by Andrew »

Putting the FEN string into google comes up with a number of discussions including the following from the Rybka forums:

http://rybkaforum.net/cgi-bin/rybkaforu ... ?tid=25995

It appears null move reductions make a lot of engines slower to find this. The latest Komodo 12.1.1 gets his in under a minute if you turn off "null move pruning" in the UCI options. Unfortunately Shredder doesn't have this option.
Dann Corbit
Posts: 12638
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: Mario Matous study from 1975 solved by Stockfish

Post by Dann Corbit »

Solved easily by ChestUci many years ago. Here are the parameters:
#13; 00:08 @ C0/R7/K4/P0/X35
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
peter
Posts: 3236
Joined: Sat Feb 16, 2008 7:38 am
Full name: Peter Martan

Re: Mario Matous study from 1975 solved by Stockfish

Post by peter »

Dann Corbit wrote: Thu Jun 28, 2018 8:32 pm Solved easily by ChestUci many years ago. Here are the parameters:
#13; 00:08 @ C0/R7/K4/P0/X35
Yes, Dann, of course it isn't a big problem for a mate solving program, neither for SF MateFinder, as I showed in my posting above.

Yet I find it interesting to see, that SF dev. with "normal" null move verification does find the mate in 13 in less then ten minutes on single core nowadays.
Peter.
Dann Corbit
Posts: 12638
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: Mario Matous study from 1975 solved by Stockfish

Post by Dann Corbit »

But SF has a much harder time with the mate in 8 shown by Tirsa Poppins.
Partly a mobility problem, I think, since a tweaked version solves it reasonably fast.
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
MOBMAT
Posts: 390
Joined: Sat Feb 04, 2017 11:57 pm
Location: USA

Re: Mario Matous study from 1975 solved by Stockfish

Post by MOBMAT »

The position

Code: Select all

FEN: n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - 0 1
appears to be the parent position of:

Code: Select all

FEN: n1QBq1k1/5p1p/5KP1/p7/8/8/8/8 w - -
I've seen this position appear in a lot of suites and "Engines can't find this mate" web page diatribes.
The latter is mate in 12, starting with c7. We reach the position after playing Qc8 followed by Kg8 from the original position. I guess the original was too "tough", so the first couple of moves were made and republished in an attempt to make it easier.
If engines that can't solve the child position, they probably won't be able to handle the parent.
I ran some engines against the child position. Here are the results (winning move c7). Each engine searched for 2 minutes or till they reached 24 ply. In a few situations, I terminated the search if it was going to take too long. I tried many other engines but if they were too slow, they were not included.

Only one winner... Komodo 9, but it could only do it with Null Move disabled.

Code: Select all

All engines tested on an i5-2450M 2.60Ghz laptop, one core, 1Gb Hash, 2min or 24 ply, no endgame TBs			
Tests run on Arena 3.51			
FEN:	n1QBq1k1/5p1p/5KP1/p7/8/8/8/8 w - - 0 1 		
Engine		Depth/Eval	NM / LMR (1)	Move
Andscacs 0.93	38 / +0.01	Yes / 		gxh7+
Andscacs 0.93	37 / +0.01	No /		gxh7+
Booot 6.2	24 / +0.08	default		gxh7+
Critter 1.6a	24/ 0.00	default		gxh7+
Equnox 3.30	27 / 0.00	default		gxh7+
Fire 7.1	24 / 0.00 (*)	default		gxh7+
Fizbo 2		24 / +1.12 (*)	default		gxh7+
Houdini 1.5a	26 / 0.00	default		gxh7+
Houdini 6 (%)	27 / +0.12	default		gxh7+
Komodo 9.02	29 / +0.08	Yes / Yes	gxh7+
Komodo 9.02	22 / M12	No / Yes	Bc7
Komodo 9.02	22 / +0.09 (2)	Yes / No	gxh7+
Komodo 9.02	15 / M12	No / No	Bc7	gxh7+
MOBMAT 2018a (3)24 / +2.53 (*)	No / Yes	gxh7+
MOBMAT 2018a (3)24 /  +2.63	Yes / Yes	gxh7+
MOBMAT 2018a (3)17 / +2.43 (*)	Yes / No	gxh7+
MOBMAT 2018a (3)17 / +2.59 (*)	No / No		gxh7+
Pedone 1.6	27 / +1.38	default		gxh7+
Stockfish 9	37 / +0.08	default		gxh7+
SF_18062711	40 / +0.08	default		gxh7+
Texel v107	22 / 0.00 (2)	Yes /		gxh7+
Texel v107	20 / 0.00 (2)	No /		gxh7+
Amoeba 2.5	28 / +0.96	default		gxh7+
Arasan 20.4	29 / 0.00	default		gxh7+
BlackMamba 2.0	24 / 0.00 (*)	default		gxh7+
Bobcat 8.0	28 / 0.00	default		gxh7+
Cheng 4.39	24 / +0.05	Yes /		gxh7+
Cheng 4.39	21 / 0.00 (*)	No /		gxh7+
Crafty 25.2	25 / +0.18	default		gxh7+
Gull 3.1	24 / 0.00	default		gxh7+
Hakkapeliitta 3.0 33 / +1.36	default		gxh7+
Ice 3.0		37 / 0.00	default		gxh7+
Mars 3.35	25 / +0.04	default		gxh7+
Naum 4.6	24 / +0.03	default		gxh7+
Nivanachess 2.4	34 / 0.00	default		gxh7+
Rodent III	31 / 0.00	default		gxh7+
Scorpio 2.8	31 / +0.31	default		gxh7+
Scorpio 2.8 MC	30 / +0.27	default		gxh7+
Senpai 2.0	24 / +0.32	default		gxh7+
SmarThink 1.97	24 / 0.00	default		gxh7+
Spike 1.4	24 / 0.00	default		gxh7+
Strelka 6	26 / 0.00	default		gxh7+
Vajolet 2.2.5	24 / 0.00	default		gxh7+
			
(*) Did not achieve 24 ply in 2 min			
(%) Tactical mode 1			
(1) LMR shown for those engines that have UCI controls			
(2) Too slow, moving on			
(3) Author's engine			
i7-6700K @ 4.00Ghz 32Gb, Win 10 Home, EGTBs on PCI SSD
Benchmark: Stockfish15.1 NNUE x64 bmi2 (nps): 1277K
Andrew
Posts: 231
Joined: Thu Mar 09, 2006 12:51 am
Location: Australia

Re: Mario Matous study from 1975 solved by Stockfish

Post by Andrew »

I've also discovered Komodo 9 (plus the latest 12.1 version) will find Bc7 in seconds if you leave it on default settings but increase to two or four in multiPV mode in Chessbase. Would be interesting to know if any other engines behave this way.

Andrew
bnst
Posts: 87
Joined: Tue Sep 11, 2007 12:16 pm

Re: Mario Matous study from 1975 solved by Stockfish

Post by bnst »

Very nice table. Thanks !

I have also noted that the study is the parent of the common test position n1QBq1k1/5p1p/5KP1/p7/8/8/8/8 w - -
So I checked alle the possible squares for the queen which give rise to the Bc7 solution. I found these five:
n2Bqk2/5p1p/Q4KP1/p7/8/8/8/8 w - - bm Qc8;
n2Bqk2/5p1p/5KP1/p4Q2/8/8/8/8 w - - bm Qc8;
n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - bm Qc8;
n2Bqk2/5p1p/5KP1/p7/8/2Q5/8/8 w - - bm Qc8;
n2Bqk2/5p1p/5KP1/p7/8/8/2Q5/8 w - - bm Qc8;

Stockfish 180613 solves all of them: (I show when Qc8 is first found and the time for finding the mate)
FEN: n2Bqk2/5p1p/Q4KP1/p7/8/8/8/8 w - - 0 1
Stockfish_180613: 72/24+ 45:05 5 997 832 972 2 217 020 +0,07 Qc8
72/26 45:44 6 099 678 888 2 222 181 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Nd5+ Ke6+ Nc3 Bxc3+ Qxc3 f8Q+

FEN: n2Bqk2/5p1p/5KP1/p4Q2/8/8/8/8 w - - 0 1
Stockfish_180613: 80/24+ 2:00:53 16 236 505 627 2 238 399 +0,07 Qc8
80/26 2:04:29 16 770 464 979 2 245 063 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Nb5 Ke6+ Nc3 Bxc3+ Qxc3 f8Q+

FEN: n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - 0 1
Stockfish_180613: 8/11 00:00 5 922 394 800 +0,36 Qc8 Kg8 gxh7+ Kh8 Qxa8 Qe6+ Kg5 Kxh7 Qxa5 Kg7 Qc3+ Kg8
62/26 09:28 1 294 970 729 2 277 592 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Nb5 Ke6+ Nc3 Bxc3+ Qxc3 f8Q+

FEN: n2Bqk2/5p1p/5KP1/p7/8/2Q5/8/8 w - - 0 1
Stockfish_180613: 70/24+ 31:24 4 086 845 870 2 168 237 +0,07 Qc8
70/26 32:19 4 217 983 867 2 174 870 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Qc3+ Bxc3 Nd5+ Kg5+ Nxc3 f8Q+

FEN: n2Bqk2/5p1p/5KP1/p7/8/8/2Q5/8 w - - 0 1
Stockfish_180613: 84/24+ 3:17:11 25 807 959 416 2 181 347 +0,07 Qc8
84/26 3:23:08 26 663 043 453 2 187 572 +M13 Qc8 Kg8 Bc7 Qxc8 gxf7+ Kh8 Be5 Qc5 Bb2 Nc7 Ba1 a4 Bb2 a3 Ba1 a2 Bb2 a1Q Bxa1 Qe5+ Bxe5 Nd5+ Ke6+ Nf6 Bxf6+

This is run in a single thread on an I7-5820K 3.3GHz processor witg 4GB hash and 6-man Syzygy EGTBs.

It seems that the most difficult, at least for Stockfish, is number five where the queen is on c2.

Regards
Andreas
Dann Corbit
Posts: 12638
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: Mario Matous study from 1975 solved by Stockfish

Post by Dann Corbit »

bnst wrote: Fri Jun 29, 2018 12:57 pm Very nice table. Thanks !

I have also noted that the study is the parent of the common test position n1QBq1k1/5p1p/5KP1/p7/8/8/8/8 w - -
So I checked alle the possible squares for the queen which give rise to the Bc7 solution. I found these five:
n2Bqk2/5p1p/Q4KP1/p7/8/8/8/8 w - - bm Qc8;
n2Bqk2/5p1p/5KP1/p4Q2/8/8/8/8 w - - bm Qc8;
n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - bm Qc8;
n2Bqk2/5p1p/5KP1/p7/8/2Q5/8/8 w - - bm Qc8;
n2Bqk2/5p1p/5KP1/p7/8/8/2Q5/8 w - - bm Qc8;
{snip}
Here is a bigger set to accomplish the same thing:

Code: Select all

n2Bqk2/3Q1p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P1aS1";
n2Bqk2/5p1p/4QKP1/p7/8/8/8/8 w - - pv Qc8; id "P1aS2";
n2Bqk2/5p1p/5KP1/p4Q2/8/8/8/8 w - - pv Qc8; id "P1aS3";
n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - pv Qc8; id "P1aS4";
n2Bqk2/5p1p/5KP1/p7/8/7Q/8/8 w - - pv Qc8; id "P1aS5";
n2Bqk2/2Q2p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P1aS6";
n2Bqk2/5p1p/2Q2KP1/p7/8/8/8/8 w - - pv Qc8; id "P1aS7";
n2Bqk2/5p1p/5KP1/p7/2Q5/8/8/8 w - - pv Qc8; id "P1aS8";
n2Bqk2/5p1p/5KP1/p7/8/2Q5/8/8 w - - pv Qc8; id "P1aS9";
n2Bqk2/5p1p/5KP1/p7/8/8/2Q5/8 w - - pv Qc8; id "P1aS10";
n2Bqk2/5p1p/5KP1/p7/8/8/8/2Q5 w - - pv Qc8; id "P1aS11";
n2Bqk2/1Q3p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P1aS12";
n2Bqk2/5p1p/Q4KP1/p7/8/8/8/8 w - - pv Qc8; id "P1aS13";
nQ1Bqk2/5p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P1aS14";
2kqB2n/p1p1Q3/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P1bS1";
2kqB2n/p1p5/1PKQ4/7p/8/8/8/8 w - - pv Qf8; id "P1bS2";
2kqB2n/p1p5/1PK5/2Q4p/8/8/8/8 w - - pv Qf8; id "P1bS3";
2kqB2n/p1p5/1PK5/7p/1Q6/8/8/8 w - - pv Qf8; id "P1bS4";
2kqB2n/p1p5/1PK5/7p/8/Q7/8/8 w - - pv Qf8; id "P1bS5";
2kqB2n/p1p2Q2/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P1bS6";
2kqB2n/p1p5/1PK2Q2/7p/8/8/8/8 w - - pv Qf8; id "P1bS7";
2kqB2n/p1p5/1PK5/7p/5Q2/8/8/8 w - - pv Qf8; id "P1bS8";
2kqB2n/p1p5/1PK5/7p/8/5Q2/8/8 w - - pv Qf8; id "P1bS9";
2kqB2n/p1p5/1PK5/7p/8/8/5Q2/8 w - - pv Qf8; id "P1bS10";
2kqB2n/p1p5/1PK5/7p/8/8/8/5Q2 w - - pv Qf8; id "P1bS11";
2kqB2n/p1p3Q1/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P1bS12";
2kqB2n/p1p5/1PK4Q/7p/8/8/8/8 w - - pv Qf8; id "P1bS13";
2kqB1Qn/p1p5/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P1bS14";
8/8/8/8/P7/5kp1/3q1P1P/N2bQK2 b - - pv Qc1; id "P1cS1";
8/8/8/8/P7/4qkp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS2";
8/8/8/8/P4q2/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS3";
8/8/8/6q1/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS4";
8/8/7q/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS5";
8/8/8/8/P7/5kp1/2q2P1P/N2bQK2 b - - pv Qc1; id "P1cS6";
8/8/8/8/P7/2q2kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS7";
8/8/8/2q5/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS8";
8/8/2q5/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS9";
8/2q5/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS10";
2q5/8/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS11";
8/8/8/8/P7/5kp1/1q3P1P/N2bQK2 b - - pv Qc1; id "P1cS12";
8/8/8/8/P7/q4kp1/5P1P/N2bQK2 b - - pv Qc1; id "P1cS13";
8/8/8/8/P7/5kp1/5P1P/Nq1bQK2 b - - pv Qc1; id "P1cS14";
8/8/8/8/7P/1pk5/P1P1q3/2KQb2N b - - pv Qf1; id "P1dS1";
8/8/8/8/7P/1pkq4/P1P5/2KQb2N b - - pv Qf1; id "P1dS2";
8/8/8/8/2q4P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P1dS3";
8/8/8/1q6/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P1dS4";
8/8/q7/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P1dS5";
8/8/8/8/7P/1pk5/P1P2q2/2KQb2N b - - pv Qf1; id "P1dS6";
8/8/8/8/7P/1pk2q2/P1P5/2KQb2N b - - pv Qf1; id "P1dS7";
8/8/8/5q2/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P1dS8";
8/8/5q2/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P1dS9";
8/5q2/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P1dS10";
5q2/8/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P1dS11";
8/8/8/8/7P/1pk5/P1P3q1/2KQb2N b - - pv Qf1; id "P1dS12";
8/8/8/8/7P/1pk4q/P1P5/2KQb2N b - - pv Qf1; id "P1dS13";
8/8/8/8/7P/1pk5/P1P5/2KQb1qN b - - pv Qf1; id "P1dS14";
n2Bqk2/3Q1p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P2aS1";
n2Bqk2/5p1p/4QKP1/p7/8/8/8/8 w - - pv Qc8; id "P2aS2";
n2Bqk2/5p1p/5KP1/p4Q2/8/8/8/8 w - - pv Qc8; id "P2aS3";
n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - pv Qc8; id "P2aS4";
n2Bqk2/5p1p/5KP1/p7/8/7Q/8/8 w - - pv Qc8; id "P2aS5";
n2Bqk2/2Q2p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P2aS6";
n2Bqk2/5p1p/2Q2KP1/p7/8/8/8/8 w - - pv Qc8; id "P2aS7";
n2Bqk2/5p1p/5KP1/p7/2Q5/8/8/8 w - - pv Qc8; id "P2aS8";
n2Bqk2/5p1p/5KP1/p7/8/2Q5/8/8 w - - pv Qc8; id "P2aS9";
n2Bqk2/5p1p/5KP1/p7/8/8/2Q5/8 w - - pv Qc8; id "P2aS10";
n2Bqk2/5p1p/5KP1/p7/8/8/8/2Q5 w - - pv Qc8; id "P2aS11";
n2Bqk2/1Q3p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P2aS12";
n2Bqk2/5p1p/Q4KP1/p7/8/8/8/8 w - - pv Qc8; id "P2aS13";
nQ1Bqk2/5p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P2aS14";
2kqB2n/p1p1Q3/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P2bS1";
2kqB2n/p1p5/1PKQ4/7p/8/8/8/8 w - - pv Qf8; id "P2bS2";
2kqB2n/p1p5/1PK5/2Q4p/8/8/8/8 w - - pv Qf8; id "P2bS3";
2kqB2n/p1p5/1PK5/7p/1Q6/8/8/8 w - - pv Qf8; id "P2bS4";
2kqB2n/p1p5/1PK5/7p/8/Q7/8/8 w - - pv Qf8; id "P2bS5";
2kqB2n/p1p2Q2/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P2bS6";
2kqB2n/p1p5/1PK2Q2/7p/8/8/8/8 w - - pv Qf8; id "P2bS7";
2kqB2n/p1p5/1PK5/7p/5Q2/8/8/8 w - - pv Qf8; id "P2bS8";
2kqB2n/p1p5/1PK5/7p/8/5Q2/8/8 w - - pv Qf8; id "P2bS9";
2kqB2n/p1p5/1PK5/7p/8/8/5Q2/8 w - - pv Qf8; id "P2bS10";
2kqB2n/p1p5/1PK5/7p/8/8/8/5Q2 w - - pv Qf8; id "P2bS11";
2kqB2n/p1p3Q1/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P2bS12";
2kqB2n/p1p5/1PK4Q/7p/8/8/8/8 w - - pv Qf8; id "P2bS13";
2kqB1Qn/p1p5/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P2bS14";
8/8/8/8/P7/5kp1/3q1P1P/N2bQK2 b - - pv Qc1; id "P2cS1";
8/8/8/8/P7/4qkp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS2";
8/8/8/8/P4q2/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS3";
8/8/8/6q1/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS4";
8/8/7q/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS5";
8/8/8/8/P7/5kp1/2q2P1P/N2bQK2 b - - pv Qc1; id "P2cS6";
8/8/8/8/P7/2q2kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS7";
8/8/8/2q5/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS8";
8/8/2q5/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS9";
8/2q5/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS10";
2q5/8/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS11";
8/8/8/8/P7/5kp1/1q3P1P/N2bQK2 b - - pv Qc1; id "P2cS12";
8/8/8/8/P7/q4kp1/5P1P/N2bQK2 b - - pv Qc1; id "P2cS13";
8/8/8/8/P7/5kp1/5P1P/Nq1bQK2 b - - pv Qc1; id "P2cS14";
8/8/8/8/7P/1pk5/P1P1q3/2KQb2N b - - pv Qf1; id "P2dS1";
8/8/8/8/7P/1pkq4/P1P5/2KQb2N b - - pv Qf1; id "P2dS2";
8/8/8/8/2q4P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P2dS3";
8/8/8/1q6/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P2dS4";
8/8/q7/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P2dS5";
8/8/8/8/7P/1pk5/P1P2q2/2KQb2N b - - pv Qf1; id "P2dS6";
8/8/8/8/7P/1pk2q2/P1P5/2KQb2N b - - pv Qf1; id "P2dS7";
8/8/8/5q2/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P2dS8";
8/8/5q2/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P2dS9";
8/5q2/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P2dS10";
5q2/8/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P2dS11";
8/8/8/8/7P/1pk5/P1P3q1/2KQb2N b - - pv Qf1; id "P2dS12";
8/8/8/8/7P/1pk4q/P1P5/2KQb2N b - - pv Qf1; id "P2dS13";
8/8/8/8/7P/1pk5/P1P5/2KQb1qN b - - pv Qf1; id "P2dS14";
n2Bqk2/3Q1p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P3aS1";
n2Bqk2/5p1p/4QKP1/p7/8/8/8/8 w - - pv Qc8; id "P3aS2";
n2Bqk2/5p1p/5KP1/p4Q2/8/8/8/8 w - - pv Qc8; id "P3aS3";
n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - pv Qc8; id "P3aS4";
n2Bqk2/5p1p/5KP1/p7/8/7Q/8/8 w - - pv Qc8; id "P3aS5";
n2Bqk2/2Q2p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P3aS6";
n2Bqk2/5p1p/2Q2KP1/p7/8/8/8/8 w - - pv Qc8; id "P3aS7";
n2Bqk2/5p1p/5KP1/p7/2Q5/8/8/8 w - - pv Qc8; id "P3aS8";
n2Bqk2/5p1p/5KP1/p7/8/2Q5/8/8 w - - pv Qc8; id "P3aS9";
n2Bqk2/5p1p/5KP1/p7/8/8/2Q5/8 w - - pv Qc8; id "P3aS10";
n2Bqk2/5p1p/5KP1/p7/8/8/8/2Q5 w - - pv Qc8; id "P3aS11";
n2Bqk2/1Q3p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P3aS12";
n2Bqk2/5p1p/Q4KP1/p7/8/8/8/8 w - - pv Qc8; id "P3aS13";
nQ1Bqk2/5p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P3aS14";
2kqB2n/p1p1Q3/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P3bS1";
2kqB2n/p1p5/1PKQ4/7p/8/8/8/8 w - - pv Qf8; id "P3bS2";
2kqB2n/p1p5/1PK5/2Q4p/8/8/8/8 w - - pv Qf8; id "P3bS3";
2kqB2n/p1p5/1PK5/7p/1Q6/8/8/8 w - - pv Qf8; id "P3bS4";
2kqB2n/p1p5/1PK5/7p/8/Q7/8/8 w - - pv Qf8; id "P3bS5";
2kqB2n/p1p2Q2/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P3bS6";
2kqB2n/p1p5/1PK2Q2/7p/8/8/8/8 w - - pv Qf8; id "P3bS7";
2kqB2n/p1p5/1PK5/7p/5Q2/8/8/8 w - - pv Qf8; id "P3bS8";
2kqB2n/p1p5/1PK5/7p/8/5Q2/8/8 w - - pv Qf8; id "P3bS9";
2kqB2n/p1p5/1PK5/7p/8/8/5Q2/8 w - - pv Qf8; id "P3bS10";
2kqB2n/p1p5/1PK5/7p/8/8/8/5Q2 w - - pv Qf8; id "P3bS11";
2kqB2n/p1p3Q1/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P3bS12";
2kqB2n/p1p5/1PK4Q/7p/8/8/8/8 w - - pv Qf8; id "P3bS13";
2kqB1Qn/p1p5/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P3bS14";
8/8/8/8/P7/5kp1/3q1P1P/N2bQK2 b - - pv Qc1; id "P3cS1";
8/8/8/8/P7/4qkp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS2";
8/8/8/8/P4q2/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS3";
8/8/8/6q1/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS4";
8/8/7q/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS5";
8/8/8/8/P7/5kp1/2q2P1P/N2bQK2 b - - pv Qc1; id "P3cS6";
8/8/8/8/P7/2q2kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS7";
8/8/8/2q5/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS8";
8/8/2q5/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS9";
8/2q5/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS10";
2q5/8/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS11";
8/8/8/8/P7/5kp1/1q3P1P/N2bQK2 b - - pv Qc1; id "P3cS12";
8/8/8/8/P7/q4kp1/5P1P/N2bQK2 b - - pv Qc1; id "P3cS13";
8/8/8/8/P7/5kp1/5P1P/Nq1bQK2 b - - pv Qc1; id "P3cS14";
8/8/8/8/7P/1pk5/P1P1q3/2KQb2N b - - pv Qf1; id "P3dS1";
8/8/8/8/7P/1pkq4/P1P5/2KQb2N b - - pv Qf1; id "P3dS2";
8/8/8/8/2q4P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P3dS3";
8/8/8/1q6/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P3dS4";
8/8/q7/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P3dS5";
8/8/8/8/7P/1pk5/P1P2q2/2KQb2N b - - pv Qf1; id "P3dS6";
8/8/8/8/7P/1pk2q2/P1P5/2KQb2N b - - pv Qf1; id "P3dS7";
8/8/8/5q2/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P3dS8";
8/8/5q2/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P3dS9";
8/5q2/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P3dS10";
5q2/8/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P3dS11";
8/8/8/8/7P/1pk5/P1P3q1/2KQb2N b - - pv Qf1; id "P3dS12";
8/8/8/8/7P/1pk4q/P1P5/2KQb2N b - - pv Qf1; id "P3dS13";
8/8/8/8/7P/1pk5/P1P5/2KQb1qN b - - pv Qf1; id "P3dS14";
n2Bqk2/3Q1p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P4aS1";
n2Bqk2/5p1p/4QKP1/p7/8/8/8/8 w - - pv Qc8; id "P4aS2";
n2Bqk2/5p1p/5KP1/p4Q2/8/8/8/8 w - - pv Qc8; id "P4aS3";
n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - pv Qc8; id "P4aS4";
n2Bqk2/5p1p/5KP1/p7/8/7Q/8/8 w - - pv Qc8; id "P4aS5";
n2Bqk2/2Q2p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P4aS6";
n2Bqk2/5p1p/2Q2KP1/p7/8/8/8/8 w - - pv Qc8; id "P4aS7";
n2Bqk2/5p1p/5KP1/p7/2Q5/8/8/8 w - - pv Qc8; id "P4aS8";
n2Bqk2/5p1p/5KP1/p7/8/2Q5/8/8 w - - pv Qc8; id "P4aS9";
n2Bqk2/5p1p/5KP1/p7/8/8/2Q5/8 w - - pv Qc8; id "P4aS10";
n2Bqk2/5p1p/5KP1/p7/8/8/8/2Q5 w - - pv Qc8; id "P4aS11";
n2Bqk2/1Q3p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P4aS12";
n2Bqk2/5p1p/Q4KP1/p7/8/8/8/8 w - - pv Qc8; id "P4aS13";
nQ1Bqk2/5p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P4aS14";
2kqB2n/p1p1Q3/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P4bS1";
2kqB2n/p1p5/1PKQ4/7p/8/8/8/8 w - - pv Qf8; id "P4bS2";
2kqB2n/p1p5/1PK5/2Q4p/8/8/8/8 w - - pv Qf8; id "P4bS3";
2kqB2n/p1p5/1PK5/7p/1Q6/8/8/8 w - - pv Qf8; id "P4bS4";
2kqB2n/p1p5/1PK5/7p/8/Q7/8/8 w - - pv Qf8; id "P4bS5";
2kqB2n/p1p2Q2/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P4bS6";
2kqB2n/p1p5/1PK2Q2/7p/8/8/8/8 w - - pv Qf8; id "P4bS7";
2kqB2n/p1p5/1PK5/7p/5Q2/8/8/8 w - - pv Qf8; id "P4bS8";
2kqB2n/p1p5/1PK5/7p/8/5Q2/8/8 w - - pv Qf8; id "P4bS9";
2kqB2n/p1p5/1PK5/7p/8/8/5Q2/8 w - - pv Qf8; id "P4bS10";
2kqB2n/p1p5/1PK5/7p/8/8/8/5Q2 w - - pv Qf8; id "P4bS11";
2kqB2n/p1p3Q1/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P4bS12";
2kqB2n/p1p5/1PK4Q/7p/8/8/8/8 w - - pv Qf8; id "P4bS13";
2kqB1Qn/p1p5/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P4bS14";
8/8/8/8/P7/5kp1/3q1P1P/N2bQK2 b - - pv Qc1; id "P4cS1";
8/8/8/8/P7/4qkp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS2";
8/8/8/8/P4q2/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS3";
8/8/8/6q1/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS4";
8/8/7q/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS5";
8/8/8/8/P7/5kp1/2q2P1P/N2bQK2 b - - pv Qc1; id "P4cS6";
8/8/8/8/P7/2q2kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS7";
8/8/8/2q5/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS8";
8/8/2q5/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS9";
8/2q5/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS10";
2q5/8/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS11";
8/8/8/8/P7/5kp1/1q3P1P/N2bQK2 b - - pv Qc1; id "P4cS12";
8/8/8/8/P7/q4kp1/5P1P/N2bQK2 b - - pv Qc1; id "P4cS13";
8/8/8/8/P7/5kp1/5P1P/Nq1bQK2 b - - pv Qc1; id "P4cS14";
8/8/8/8/7P/1pk5/P1P1q3/2KQb2N b - - pv Qf1; id "P4dS1";
8/8/8/8/7P/1pkq4/P1P5/2KQb2N b - - pv Qf1; id "P4dS2";
8/8/8/8/2q4P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P4dS3";
8/8/8/1q6/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P4dS4";
8/8/q7/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P4dS5";
8/8/8/8/7P/1pk5/P1P2q2/2KQb2N b - - pv Qf1; id "P4dS6";
8/8/8/8/7P/1pk2q2/P1P5/2KQb2N b - - pv Qf1; id "P4dS7";
8/8/8/5q2/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P4dS8";
8/8/5q2/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P4dS9";
8/5q2/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P4dS10";
5q2/8/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P4dS11";
8/8/8/8/7P/1pk5/P1P3q1/2KQb2N b - - pv Qf1; id "P4dS12";
8/8/8/8/7P/1pk4q/P1P5/2KQb2N b - - pv Qf1; id "P4dS13";
8/8/8/8/7P/1pk5/P1P5/2KQb1qN b - - pv Qf1; id "P4dS14";
n2Bqk2/3Q1p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P5aS1";
n2Bqk2/5p1p/4QKP1/p7/8/8/8/8 w - - pv Qc8; id "P5aS2";
n2Bqk2/5p1p/5KP1/p4Q2/8/8/8/8 w - - pv Qc8; id "P5aS3";
n2Bqk2/5p1p/5KP1/p7/6Q1/8/8/8 w - - pv Qc8; id "P5aS4";
n2Bqk2/5p1p/5KP1/p7/8/7Q/8/8 w - - pv Qc8; id "P5aS5";
n2Bqk2/2Q2p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P5aS6";
n2Bqk2/5p1p/2Q2KP1/p7/8/8/8/8 w - - pv Qc8; id "P5aS7";
n2Bqk2/5p1p/5KP1/p7/2Q5/8/8/8 w - - pv Qc8; id "P5aS8";
n2Bqk2/5p1p/5KP1/p7/8/2Q5/8/8 w - - pv Qc8; id "P5aS9";
n2Bqk2/5p1p/5KP1/p7/8/8/2Q5/8 w - - pv Qc8; id "P5aS10";
n2Bqk2/5p1p/5KP1/p7/8/8/8/2Q5 w - - pv Qc8; id "P5aS11";
n2Bqk2/1Q3p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P5aS12";
n2Bqk2/5p1p/Q4KP1/p7/8/8/8/8 w - - pv Qc8; id "P5aS13";
nQ1Bqk2/5p1p/5KP1/p7/8/8/8/8 w - - pv Qc8; id "P5aS14";
2kqB2n/p1p1Q3/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P5bS1";
2kqB2n/p1p5/1PKQ4/7p/8/8/8/8 w - - pv Qf8; id "P5bS2";
2kqB2n/p1p5/1PK5/2Q4p/8/8/8/8 w - - pv Qf8; id "P5bS3";
2kqB2n/p1p5/1PK5/7p/1Q6/8/8/8 w - - pv Qf8; id "P5bS4";
2kqB2n/p1p5/1PK5/7p/8/Q7/8/8 w - - pv Qf8; id "P5bS5";
2kqB2n/p1p2Q2/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P5bS6";
2kqB2n/p1p5/1PK2Q2/7p/8/8/8/8 w - - pv Qf8; id "P5bS7";
2kqB2n/p1p5/1PK5/7p/5Q2/8/8/8 w - - pv Qf8; id "P5bS8";
2kqB2n/p1p5/1PK5/7p/8/5Q2/8/8 w - - pv Qf8; id "P5bS9";
2kqB2n/p1p5/1PK5/7p/8/8/5Q2/8 w - - pv Qf8; id "P5bS10";
2kqB2n/p1p5/1PK5/7p/8/8/8/5Q2 w - - pv Qf8; id "P5bS11";
2kqB2n/p1p3Q1/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P5bS12";
2kqB2n/p1p5/1PK4Q/7p/8/8/8/8 w - - pv Qf8; id "P5bS13";
2kqB1Qn/p1p5/1PK5/7p/8/8/8/8 w - - pv Qf8; id "P5bS14";
8/8/8/8/P7/5kp1/3q1P1P/N2bQK2 b - - pv Qc1; id "P5cS1";
8/8/8/8/P7/4qkp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS2";
8/8/8/8/P4q2/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS3";
8/8/8/6q1/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS4";
8/8/7q/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS5";
8/8/8/8/P7/5kp1/2q2P1P/N2bQK2 b - - pv Qc1; id "P5cS6";
8/8/8/8/P7/2q2kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS7";
8/8/8/2q5/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS8";
8/8/2q5/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS9";
8/2q5/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS10";
2q5/8/8/8/P7/5kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS11";
8/8/8/8/P7/5kp1/1q3P1P/N2bQK2 b - - pv Qc1; id "P5cS12";
8/8/8/8/P7/q4kp1/5P1P/N2bQK2 b - - pv Qc1; id "P5cS13";
8/8/8/8/P7/5kp1/5P1P/Nq1bQK2 b - - pv Qc1; id "P5cS14";
8/8/8/8/7P/1pk5/P1P1q3/2KQb2N b - - pv Qf1; id "P5dS1";
8/8/8/8/7P/1pkq4/P1P5/2KQb2N b - - pv Qf1; id "P5dS2";
8/8/8/8/2q4P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P5dS3";
8/8/8/1q6/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P5dS4";
8/8/q7/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P5dS5";
8/8/8/8/7P/1pk5/P1P2q2/2KQb2N b - - pv Qf1; id "P5dS6";
8/8/8/8/7P/1pk2q2/P1P5/2KQb2N b - - pv Qf1; id "P5dS7";
8/8/8/5q2/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P5dS8";
8/8/5q2/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P5dS9";
8/5q2/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P5dS10";
5q2/8/8/8/7P/1pk5/P1P5/2KQb2N b - - pv Qf1; id "P5dS11";
8/8/8/8/7P/1pk5/P1P3q1/2KQb2N b - - pv Qf1; id "P5dS12";
8/8/8/8/7P/1pk4q/P1P5/2KQb2N b - - pv Qf1; id "P5dS13";
8/8/8/8/7P/1pk5/P1P5/2KQb1qN b - - pv Qf1; id "P5dS14";
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.