Mate in 11 position for Amateurs

JVMerlino · Post by **JVMerlino** » Thu Nov 17, 2022 8:13 pm

[fen]2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28[/fen]

The current dev version of Myrddin needs just under one second, and 2.26M nodes, to spot Mate in 11 at depth 12. But, as always, The King from CM9000 is insanely fast with positions like this. It spots the mate practically instantly (roughly 0.03s), needing only 46,266 nodes to announce it at depth 1/5.

Chessnut1071 · Post by **Chessnut1071** » Fri Nov 18, 2022 6:55 am

JVMerlino wrote: ↑Thu Nov 17, 2022 8:13 pm [fen]2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28[/fen]

The current dev version of Myrddin needs just under one second, and 2.26M nodes, to spot Mate in 11 at depth 12. But, as always, The King from CM9000 is insanely fast with positions like this. It spots the mate practically instantly (roughly 0.03s), needing only 46,266 nodes to announce it at depth 1/5.

I can understand how CM9000 can find mate in 0.03s, it's easy if you hardwire the chip. Feng-Hus demonstrated that at CMU in 1988. He reached 500,000,000 nodes per second on his chess chip. Little known fact about Hsu, he was a sub 1500 tournament player, almost everybody had their way with him OTB. He was; however, responsible for beating Kasparov with Deep Blue. I was a big fan of Hans Berliner, developer of HiTech, which at the time was the best program in the world. Hans was an IM, 2400+ and programmed logic into HiTech. Hsu had the weakest evaluation I ever saw, but, he got so deep because of the incredible speed from hardwiring the chip. Even though Hsu and Hans were a few steps apart from each other, Hus never invited Hans to participate. It's a shame. I can only imagine what Hus could have done with Hans on the team.

CMU is experimenting with a quantum computer, however, it's nowhere near ready for competition. My guess at least 10-20 years, although some think 3-5 years. If it's successful, you could see speeds of 10,000s of billions nodes/sec. You could be looking at 40-ply in less than a second. Stockfish beware.

I am interested in Myrddin's solution and will try to compare with mine, which I have not yet verified at 22-ply.

Joerg Oster · Post by **Joerg Oster** » Fri Nov 18, 2022 1:33 pm

JVMerlino wrote: ↑Thu Nov 17, 2022 8:13 pm [fen]2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28[/fen]

The current dev version of Myrddin needs just under one second, and 2.26M nodes, to spot Mate in 11 at depth 12. But, as always, The King from CM9000 is insanely fast with positions like this. It spots the mate practically instantly (roughly 0.03s), needing only 46,266 nodes to announce it at depth 1/5.

Not bad!

The Huntsman Dev, 1 Thread
info depth 18 seldepth 22 multipv 1 score mate 11 nodes 1389473 nps 980573 hashfull 558 tbhits 0 time 1417 pv c7g7 g8g7 f5f6 g7h6 e5g4 h6g5 f3f5 d6f5 f1f5 g5g6 f5e5 d4d3 b1d3 g6f7 e5e7 f7g8 e7g7 g8h8 g7h7 h8g8 g4h6
bestmove c7g7 ponder g8g7

Matefish Dev, 1 Thread
info string Success! Mate in 11 found!
info depth 17 seldepth 21 multipv 1 score mate 11 nodes 277151692 nps 1394249 tbhits 0 time 198782 pv c7g7 g8g7 f5f6 g7h6 e5g4 d4g4 f3g4 d6e4 g4g7 h6h5 g7h7 h5g5 h7f5 g5h6 b1e4 f8g8 f5h7 h6g5 f1f5 g5g4 h7h5
bestmove c7g7 ponder g8g7

Steve Maughan · Post by **Steve Maughan** » Fri Nov 18, 2022 3:37 pm

This is a fascinating position. It seems The King is still an order of magnitude faster than anyone else at solving these types of positions. Stockfish 15 takes 555k nodes and a depth of 18 to see mate — others I have tested are no better.

What is amazing is the path to mate is all checks from white. In other positions I had thought The King's secret sauce was handling forced threats but this position has few threat-based paths. Clearly The King does something "special" when analyzing positions that are in check which results in a sophisticated extension of certain moves. I suspect the threshold for extending is quite high, otherwise there would be a search explosion.

Anyone else have any ideas as to how The King is handling this type of position?

— Steve

JVMerlino · Post by **JVMerlino** » Fri Nov 18, 2022 6:18 pm

Chessnut1071 wrote: ↑Fri Nov 18, 2022 6:55 am
JVMerlino wrote: ↑Thu Nov 17, 2022 8:13 pm [fen]2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28[/fen]

The current dev version of Myrddin needs just under one second, and 2.26M nodes, to spot Mate in 11 at depth 12. But, as always, The King from CM9000 is insanely fast with positions like this. It spots the mate practically instantly (roughly 0.03s), needing only 46,266 nodes to announce it at depth 1/5.
I can understand how CM9000 can find mate in 0.03s, it's easy if you hardwire the chip.

I am interested in Myrddin's solution and will try to compare with mine, which I have not yet verified at 22-ply.

It seems I must keep reminding you that The King in CM9000 is only a piece of software and contains no "chips". It's just an engine that was, for its time, REALLY good at finding mates, and even today can impress on occasion.

As for Myrddin's "solution", a check extension is your best friend in this position.

jm

JVMerlino · Post by **JVMerlino** » Fri Nov 18, 2022 6:20 pm

Steve Maughan wrote: ↑Fri Nov 18, 2022 3:37 pm This is a fascinating position. It seems The King is still an order of magnitude faster than anyone else at solving these types of positions. Stockfish 15 takes 555k nodes and a depth of 18 to see mate — others I have tested are no better.

What is amazing is the path to mate is all checks from white. In other positions I had thought The King's secret sauce was handling forced threats but this position has few threat-based paths. Clearly The King does something "special" when analyzing positions that are in check which results in a sophisticated extension of certain moves. I suspect the threshold for extending is quite high, otherwise there would be a search explosion.

Anyone else have any ideas as to how The King is handling this type of position?

— Steve

Heh, I wish I did have some inside knowledge. But Johan was very private with his code. Obviously a check extension is crucial to finding this position quickly. But The King clearly does "something more".

Ajedrecista · Post by **Ajedrecista** » Fri Nov 18, 2022 8:53 pm

Hello:

Nemjet 3.07 did reasonably well:

Code: Select all

FEN: 2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28

Nejmet 3.07:
  1/2	00:00	           3	3	+1,00	h2xg3
  1/2	00:00	          14	14	-3,00	h2xg3
  1/2	00:00	          21	21	-3,00	Rc7xb7
  1/2	00:00	          33	33	-2,27	Rc7xb7
  1/2	00:00	          34	34	-2,27	Rc7xc8
  1/2	00:00	         184	184	+1,55	Rc7xc8
  2/4	00:00	         208	208	+1,55	Rc7xc8 Rf8xc8
  2/4	00:00	         406	406	+1,55	Rc7xc8 Rf8xc8
  3/6	00:00	         509	509	+1,55	Rc7xc8
  3/6	00:00	       1.061	1.061	+0,88	Rc7xc8 Rf8xc8 Qf3f4
  3/6	00:00	       1.736	1.736	+0,88	Rc7xc8 Rf8xc8 Qf3f4
  4/8	00:00	       2.394	2.394	+0,88	Rc7xc8 Rf8xc8 Qf3f4 Qd4xd5
  4/8	00:00	       6.315	6.315	+0,88	Rc7e7
  4/8	00:00	       8.318	8.318	+0,92	Rc7e7 Nb6xd5 Rf1d1 Rc8c1
  4/8	00:00	      10.884	10.884	+0,92	Rc7e7 Nb6xd5 Rf1d1 Rc8c1
  5/10	00:00	      24.380	24.380	+0,92	Rc7e7 Nb6xd5 Rf1d1 Rc8c1 Rd1xc1
  5/10	00:00	      38.487	38.487	+0,92	Rf1d1
  5/10	00:00	      42.458	42.458	+1,93	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4f3
  5/10	00:00	      49.946	49.946	+1,93	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4f3
  6/12	00:00	      59.367	59.367	+1,76	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4f3 Rf8c8
  6/12	00:00	     101.564	101.564	+1,76	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4f3 Rf8c8
  7/14	00:00	     109.714	109.714	+1,76	Rf1d1
  7/14	00:00	     130.265	130.265	+1,40	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4f3 Rg7e7 Ne5g6
  7/14	00:00	     345.819	345.819	+1,40	Rc7e7
  7/14	00:00	     568.825	568.825	+1,71	Rc7e7 Nb6xd5 Re7e6 Nd5f6 Rf1d1 Qd4b2 h2xg3
  7/14	00:00	     673.452	673.452	+1,71	Rc7e7 Nb6xd5 Re7e6 Nd5f6 Rf1d1 Qd4b2 h2xg3
  8/16	00:01	     749.838	749.838	+1,71	Rc7e7
  8/16	00:01	   1.087.390	1.087.390	+1,26	Rc7e7 Nb6xd5 Re7e6 Rf8f6 Rf1d1 Rf6xe6 Rd1xd4 Rc8c1+ Rd4d1
  8/16	00:01	   1.164.261	1.164.261	+1,26	Rf1d1
  8/16	00:01	   1.237.443	1.237.443	+1,84	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 h2xg3 h4xg3 Qd1g4+ Rc7g7 Qg4f3 Rf8c8
  8/16	00:01	   1.582.964	1.582.964	+1,84	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 h2xg3 h4xg3 Qd1g4+ Rc7g7 Qg4f3 Rf8c8
  9/18	00:01	   1.663.256	1.663.256	+1,84	Rf1d1
  9/18	00:02	   1.856.016	928.008	+1,58	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 h2xg3 h4xg3 Qd1g4+ Rc7g7 Qg4f3 Rg7h7+ Kh1g1 Kg8h8
  9/18	00:03	   2.856.101	952.033	+1,58	Rc7g7+
  9/18	00:08	   9.214.984	1.151.873	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6h5 Qf3f5+ Nd6xf5 Rf1xf5+ Kh5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4d3 Bc2xd3+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+
  9/18	00:21	  24.362.144	1.160.102	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6h5 Qf3f5+ Nd6xf5 Rf1xf5+ Kh5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4d3 Bc2xd3+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+
 10/20	00:21	  25.231.678	1.201.508	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6h5 Qf3f5+ Nd6xf5 Rf1xf5+ Kh5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4d3 Bc2xd3+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+
 10/20	00:35	  42.291.777	1.208.336	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6h5 Qf3f5+ Nd6xf5 Rf1xf5+ Kh5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4d3 Bc2xd3+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+
 11/22	00:38	  45.533.312	1.198.245	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6h5 Qf3f5+ Nd6xf5 Rf1xf5+ Kh5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4d3 Bc2xd3+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+

------------

Prodeo 1.5 found a checkmate in 12 moves very fast but no further output after two minutes:

Code: Select all

FEN: 2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28

ProDeo 1.5:
   1	00:00	         245	245.000	+0,93	Rc7xc8 Nd6xc8
   2	00:00	       1.644	1.644.000	+0,67	Rc7xc8 Rf8xc8 Rf1e1 g3xh2
   2	00:00	       1.767	1.767.000	+0,87	Rc7e7 Nb6xd5
   2	00:00	       2.842	2.842.000	+0,87	Rf1d1
   2	00:00	       3.107	3.107.000	+1,27	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4xh4
   3	00:00	       3.902	3.902.000	+1,27	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4xh4 Nd6xf5
   3	00:00	       5.374	5.374.000	+1,30	Rc7e7 Nb6xd5 Qf3b3
   4	00:00	      11.862	11.862.000	+0,10	Rc7e7 Nb6xd5 Qf3b3 Rc8c3
   4	00:00	      13.001	13.001.000	+1,27	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4xh4 Nd6xf5
   5	00:00	      31.379	31.379.000	+1,38	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 Qd1g4+ Rc7g7 Qg4xh4 Nb6xd5
   5	00:00	      46.252	46.252.000	+1,38	Rc7xc8
   5	00:00	      69.485	69.485.000	+1,53	Rc7xc8 Rf8xc8 f5f6 Qd4xe5 Qf3g4+ Kg8f7 Qg4g6+ Kf7f8 Qg6g7+ Kf8e8 f6f7+ Nd6xf7 Qg7xf7+ Ke8d8 h2xg3 h4xg3 Qf7xb7 Qe5xd5 Qb7xa7
   6	00:00	     122.623	122.623.000	+1,53	Rc7xc8 Rf8xc8 f5f6 Qd4xe5 Qf3g4+ Kg8f7 Qg4g6+ Kf7f8 Qg6g7+ Kf8e8 f6f7+ Nd6xf7 Qg7xf7+ Ke8d8 h2xg3 h4xg3 Qf7xb7 Qe5xd5 Qb7xa7
   6	00:00	     305.187	305.187.000	+1,53	Rc7e7
   6	00:00	     490.687	490.687.000	+2,55	Rc7e7 Rc8e8 Ne5g6 Rf8f7 Rf1d1 Qd4xd1+ Qf3xd1 Re8xe7 Ng6xe7+ Rf7xe7 h2xg3 h4xg3
   7	00:00	     705.002	705.002.000	+1,65	Rc7e7 Nb6xd5 Re7d7 Rf8e8 Qf3h5 Qd4xe5 Qh5g6+ Kg8f8 Qg6h6+ Kf8g8 Rd7xd6 g3xh2
   7	00:00	     892.913	892.913.000	+2,05	Rc7xc8 Rf8xc8 Ne5g6 Rc8c7 Qf3h5 Qd4f6 Ng6xh4 g3xh2 g2g4
   7	00:00	   1.119.008	1.119.008.000	+2,05	Rc7g7+
   7	00:00	   1.191.771	1.191.771.000	+2,05	Rc7g7+
   7	00:01	   2.119.219	2.119.219.000	+19,44	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Qd4xg4 Qf3xg4 Rc8c2 Qg4xh4+ Kh6g6 Bb1xc2+ Nd6f5 Bc2xf5+ Kg6f7 Bf5e6+ Kf7g6 h2xg3
   8	00:01	   2.506.275	2.506.275	+M12	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+ Kg5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4d3 Bc2xd3+ Kg6f7 Re5e7+ Kf7g8 Re7g7+ Kg8h8 Rg7h7+ Kh8g8 Ng4h6+

------------

Ruffian 1.05 was very fast:

Code: Select all

FEN: 2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28

Ruffian 1.0.5:
  1/4	00:00	           9	0	-2,56	h2xg3 Rc8xc7
  1/4	00:00	          21	0	+1,84	Rc7xc8 Rf8xc8
  2/8	00:00	         991	0	+1,31	Rc7xc8 Rf8xc8 Rf1e1
  2/8	00:00	       1.085	0	+1,60	Rc7e7 Nb6xd5
  3/10	00:00	       6.250	312.500	+1,73	Rc7e7 Nb6xd5 Rf1d1
  4/13	00:00	      13.665	683.250	+1,74	Rc7e7 Nb6xd5 Rf1d1 Rc8c1
  5/15	00:00	      45.797	1.526.566	+1,14	Rc7e7 Nb6xd5 Re7e6 Nd5e3 Re6g6+ Kg8h8
  5/15	00:00	      68.048	2.268.266	+1,98	Rc7xc8 Rf8xc8 Ne5g6 Rc8c3 Qf3h5 Nb6xd5 Ng6xh4 g3xh2 Kh1xh2
  6/16	00:00	     119.067	2.381.340	+1,98	Rc7xc8 Rf8xc8 Ne5g6 Rc8c3 Qf3h5 Nb6xd5 Ng6xh4 g3xh2 Kh1xh2
  7/18	00:00	     330.732	2.544.092	+2,24	Rc7xc8 Rf8xc8 Ne5g6 Rc8c3 Qf3h5 Nb6xd5 Rf1d1 Qd4c5 Ng6xh4
  8/21	00:00	     973.165	2.780.471	+2,50	Rc7xc8 Rf8xc8 Ne5g6 Rc8c3 Qf3h5 g3xh2 Rf1d1 Qd4f6 Kh1xh2 Rc3c4
  8/23	00:00	   2.194.448	2.813.394	+2,51	Rc7e7 Nb6xd5 Re7e6 Nd5f6 Rf1d1 Qd4b2 h2xg3 Rc8c3
  8/29	00:01	   3.389.416	2.848.248	+7,50	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+ Kg5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4e4 Bc2xe4+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8
  9/29+	00:01	   4.123.225	2.804.914	+7,85	Rc7g7+
  9/29	00:01	   5.414.345	2.974.914	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+ Kg5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4e4 Bc2xe4+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+
 10/29	00:02	   6.092.828	3.046.414	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+ Kg5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4e4 Bc2xe4+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+
 11/29	00:02	   7.148.458	3.149.100	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+ Kg5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4e4 Bc2xe4+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+
 12/29	00:03	  12.459.858	3.423.037	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+ Kg5g6 Rf5e5+ Rc8c2 Bb1xc2+ Qd4e4 Bc2xe4+ Kg6f7 Re5e7+ Kf7g8 Ng4h6+ Kg8h8 Re7h7+

------------

Rybka 2.2 was also fast:

Code: Select all

FEN: 2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28

Rybka 2.2 64 bit:
   2	00:00	       2.246	48.934	+1,35	Rf1d1
   3	00:00	       4.277	93.184	+1,27	Rf1d1
   4	00:00	       5.450	118.740	+1,24	Rf1d1
   5	00:00	      26.632	290.118	+1,08	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7
   6	00:00	      42.914	348.761	+1,07	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 h2xg3
   7	00:00	     136.246	405.569	+0,88	Rf1d1 Qd4xd1+ Qf3xd1 Rc8xc7 h2xg3 h4xg3 Bb1c2
   7	00:00	     186.782	407.814	+1,29	Rc7xc8 Rf8xc8 Ne5g6 Rc8c3 Qf3h5
   7	00:00	     188.962	412.573	+1,69	Rc7e7 Nb6xd5 Re7e6 Rf8f6 Qf3h5
   8	00:00	     189.860	400.859	+1,69	Rc7e7 Nb6xd5 Re7e6 Rf8f6 Qf3h5
   9	00:00	     250.220	389.992	+2,05	Rc7e7 Nb6xd5 Re7e6 Rf8f6 Qf3h5 Qd4f4
  10	00:01	     690.248	400.234	+2,28	Rc7e7 Rc8e8 Ne5g6 Re8xe7 Ng6xe7+
  11	00:03	   1.523.683	415.956	+6,31	Rc7e7 Rc8c7 Re7xc7 Rf8c8 Rc7xc8+ Nb6xc8 Qf3f4 Qd4xf4 Rf1xf4 Nc8b6 Rf4g4+ Kg8f8
  11	00:03	   1.566.592	420.716	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+
  12	00:03	   1.596.201	423.448	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+
  13	00:04	   1.678.625	436.493	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+
  14	00:04	   1.927.605	471.315	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+
  15	00:04	   2.271.018	518.511	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+
  16	00:05	   3.135.392	609.692	+M11	Rc7g7+ Kg8xg7 f5f6+ Kg7h6 Ne5g4+ Kh6g5 Qf3f5+ Nd6xf5 Rf1xf5+

Regards from Spain.

Ajedrecista.

Sazgr · Post by **Sazgr** » Fri Nov 18, 2022 9:31 pm

Actually a mate that my engine can solve!

(with check extensions)

Code: Select all

position fen 2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - - 0 28
go infinite
info score cp 131 depth 1 nodes 195 nps 114557 time 1 pv c7c8
info score cp 131 depth 2 nodes 526 nps 136658 time 3 pv c7c8 f8c8
info score cp 80 depth 3 nodes 2794 nps 531461 time 5 pv c7c8 f8c8 e5g6
info score cp 80 depth 4 nodes 9425 nps 1354361 time 6 pv c7c8 f8c8 e5g6 g3h2
info score cp 101 depth 5 nodes 31899 nps 2853628 time 11 pv c7c8 f8c8 e5g6 c8c3 g6e7
info score cp 134 depth 6 nodes 246041 nps 5401108 time 45 pv f1d1 d4d1 f3d1 c8c7 d1g4 c7g7 g4f3 g8h8
info score cp 156 depth 7 nodes 613309 nps 5610474 time 109 pv c7e7 f8e8 e5g6 c8c3 f5f6 e8e7 g6e7
info score cp 138 depth 8 nodes 2308884 nps 5997948 time 384 pv c7c8 f8c8 e5g6 c8c3 f3h5 h4h3 h5h3 g3h2
info score cp 176 depth 9 nodes 5728508 nps 6091551 time 940 pv c7e7 b6d5 e7e6 f8f6 f3h5 h4h3 h5g5 g8h7 g5h5 h7g8 h5g5
info score cp 462 depth 10 nodes 22462073 nps 6273526 time 3580 pv c7g7 g8g7 f5f6 g7h6 e5g4 h6g5 f3f5 d6f5 f1f5 g5g6 f5e5 c8c2 b1c2 d4d3 c2d3 g6f7 e5e7 f7g8 e7g7
info score mate 11 depth 11 nodes 32577767 nps 6401339 time 5089 pv c7g7 g8g7 f5f6 g7h6 e5g4 h6g5 f3f5 d6f5 f1f5 g5g6 f5e5 c8c2 b1c2 d4d3 c2d3 g6f7 e5e7 f7g8 g4h6 g8h8 e7h7

Steve Maughan · Post by **Steve Maughan** » Fri Nov 18, 2022 9:32 pm

Maverick is also quite fast at solving (1 second and 7 million nodes) but this is still much slower than 32k nodes used by The King. Maverick has check extensions and checks in the first ply of the quiescent search

[fen]2r2rk1/ppR5/1n1n4/3PNP2/3q3p/5Qp1/P5PP/1B3R1K w - -[/fen]

Engine: Maverick 1.5 x64 (512 MB) by Steve Maughan

12/38 0:01 +8.18 1.Rh7 Rc7 2.Rxc7 Rc8 3.Qf4 Qxf4
4.Rxc8+ Ndxc8 5.Rxf4 Nxd5 6.Rxh4 gxh2
7.Kxh2 (6.248.818) 4469

13/38 0:01 +8.18 1.Rh7 Rc7 2.Rxc7 Rc8 3.Qf4 Qxf4
4.Rxc8+ Ndxc8 5.Rxf4 Nxd5 6.Rxh4 gxh2
7.Kxh2 (6.690.881) 4469

13/38 0:01 +8.19++ 1.Rg7+ (6.890.692) 4469

13/38 0:01 +M11 1.Rg7+ Kxg7 2.f6+ Kh6 3.Ng4+ Kg5
4.Qf5+ Nxf5 5.Rxf5+ Kg6 6.Re5+ Rc2
7.Bxc2+ Qe4 8.Bxe4+ Kf7 9.Re7+ Kg8
10.Nh6+ Kh8 11.Rh7+ (7.190.286) 4469

Witek · Post by **Witek** » Fri Nov 18, 2022 9:35 pm

Here's multi-PV Stockfish 15 analysis after 2 hours (230 billion nodes).
Looks like both Rg7 and Rh7 are M11

Code: Select all

info depth 47 seldepth 22 multipv 1 score mate 11 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv c7g7 g8g7 f5f6 g7h6 e5g4 h6g5 f3f5 d6f5 f1f5 g5g6 f5e5 c8c2 b1c2 d4d3 c2d3 g6f7 e5e7 f7g8 g4h6 g8h8 e7h7
info depth 47 seldepth 22 multipv 2 score mate 11 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv c7h7 f8f7 f5f6 f7h7 b1h7 g8f8 f3h5 d4f4 h7d3 f4e5 h5e5 d6f5 d3f5 b6d5 e5d6 f8g8 d6e6 g8f8 f5g6 d5c3 e6c8
info depth 47 seldepth 28 multipv 3 score mate 14 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv c7e7 f8f7 f5f6 b6d5 e5f7 d4f6 f7e5 f6e7 f3d5 g8g7 d5d4 g7g8 e5g6 e7g7 d4d6 g7f7 g6e7 g8g7 f1f7 g7f7 e7c8 g3h2 d6g6 f7f8 g6f6 f8g8 c8e7
info depth 47 seldepth 57 multipv 4 score mate 30 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv c7b7 d6b7 f5f6 c8c7 f3f5 f8f6 f5g5 c7g7 g5f6 d4f2 f6e6 g8f8 b1d3 h4h3 e6h3 f8e7 h3e6 e7f8 e5g6 g7g6 e6g6 b6d7 f1f2 g3f2 g6h6 f8e7 h6e6 e7d8 d5d6 b7d6 e6d6 d8e8 d3b5 f2f1q b5f1 d7b6 d6c7 e8f8 c7b8 f8e7 b8a7 b6d7 f1b5 e7d6 a7d7 d6c5 b5a6 c5b4 d7d6 b4c3 d6d3 c3b2 d3d2 b2b1 a6d3 b1a1 d2c1 a1a2
info depth 46 seldepth 82 multipv 5 score cp 1485 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv c7c8 f8c8 f5f6 d4e5 f3g4 g8f8 g4g7 f8e8 b1f5 e8d8 f5e6 c8c7 g7f8 d6e8 f6f7 c7f7 f8f7 h4h3 e6h3 e5e7 f7f4 e8d6 f4g3 b6c4 h3e6 e7h7 h2h4 h7h5 f1e1 d8c7 e6g4 h5h8 e1e6 h8d4 h4h5 c7b6 h5h6 b6c5 h6h7 d4h8 g3h4 a7a5 g4h3 c5b5 h1h2 a5a4 h4e7 h8b8 g2g3 b8h8 e6f6 a4a3 f6f8 h8b2 h3g2 b2a2 h7h8q a2b2 h8h4 b2e5 e7e5 c4e5 h4d4 e5c4 g2f1 b5b4 g3g4 b7b5 g4g5 b4a5
info depth 46 seldepth 72 multipv 6 score cp 921 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv f1d1 d4d1 f3d1 c8c7 h2g3 f8e8 d1g4 c7g7 e5g6 b6d7 g4f4 d6f7 g3h4 d7f6 f4d2 a7a5 b1d3 e8d8 d2b2 d8d6 b2b7 d6d8 b7b2 d8d6 h1g1 f7d8 b2b8 f6e8 d3e4 g7b7 b8a8 e8g7 a8c8 g7e8 g1h2 b7c7 c8a8 a5a4 e4f3 c7d7 g6f4 d6h6 h2h3 e8d6 g2g3 h6f6 f4h5 f6f5 f3g4 f5h5 g4d7 d6f7 d7e6 g8g7 a8a4 h5h6 e6f7 d8f7 a4a7 g7f8 h3h2
info depth 46 seldepth 82 multipv 7 score cp 832 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv f5f6 c8c7 f3h5 c7g7 h5h6 f8f7 e5f7 g7f7 h6g5 g8h8 b1g6 f7f6 g5f6 d4f6 f1f6 b6c8 g6e8 d6e4 f6f4 e4d6 f4h4 h8g7 h4g4 g7f8 e8d7 c8b6 d7a4 g3h2 g4g6 d6f7 a4b3 b6c8 b3c2 c8b6 g6e6 f7g5 e6e1 b6c4 c2d3 c4d6 h1h2 d6c8 d3c2 f8g7 e1e5 g5f7 e5e6 f7d6 c2g6 a7a6 g6c2 g7f8 g2g4 d6b5 g4g5 b5c7 e6h6 c7e8 c2g6 e8d6 g6f5 d6f7 h6f6 c8d6 f5e6 f8g7 e6f7
info depth 46 seldepth 83 multipv 8 score cp 831 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv f3h5 c8c7 f5f6 c7g7 h5h6 f8f7 e5f7 g7f7 h6g5 g8h8 b1g6 f7f6 g5f6 d4f6 f1f6 b6c8 g6e8 d6e4 f6f4 e4d6 f4h4 h8g7 h4g4 g7f8 e8d7 c8b6 d7a4 g3h2 g4g6 d6f7 a4b3 b6c8 b3c2 c8b6 g6e6 f7d8 e6e1 d8f7 c2g6 f7h8 e1e8 f8g7 g6e4 h8f7 e8e6 g7f8 d5d6 f7d8 e6f6 f8g7 f6g6 g7f7 g2g4 b6d7 g6h6 d7f8 g4g5 f7g7 d6d7 g7f7 e4f5 f7e7 h6h3 e7d6 g5g6 f8g6 h3h6 d6e5 h6g6 e5f5 g6g8 d8c6 g8e8 f5f4
info depth 46 seldepth 92 multipv 9 score cp 593 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv c7c6 d4e5 f5f6 f8f7 f3g4 g8f8 g4h4 f8e8 c6c8 b6c8 b1g6 e8d8 g6f7 d6f7 h4g3 e5d5 f1e1 c8d6 g3e3 d8d7 e3e7 d7c6 e1c1 d6c4 e7e2 c6c5 e2e3 c5c6 e3a7 f7e5 a7a4 c6b6 a4b3 b6c6 b3d1 b7b5 d1d5 c6d5 g2g4 d5e6 g4g5 e5f3 a2a4 f3g5 a4b5 c4d6 b5b6 e6f6 c1c7 g5e6 c7d7 d6f5 b6b7 e6c5 d7c7 c5b7 c7b7 f6g5 h1g2 g5g4 b7b4 g4g5 g2f3 f5h4 f3f2 h4f5 b4b6 f5e7 f2g3 e7f5 g3h3 f5e3 b6b4 e3f5 b4e4
info depth 46 seldepth 19 multipv 10 score cp 0 nodes 229066138958 nps 27997534 hashfull 1000 tbhits 0 time 8181654 pv e5c6 b7c6 c7c8 b6c8 f5f6 c6d5 b1g6 d4e5 f6f7 d6f7 g6f7 g8h8 f3g4 c8d6 g4h4 h8g7 h4g4 g7h8

Mate in 11 position for Amateurs

Mate in 11 position for Amateurs

Re: Mate in 11 position for Amateurs

Re: Mate in 11 position for Amateurs

Re: Mate in 11 position for Amateurs

Re: Mate in 11 position for Amateurs

Re: Mate in 11 position for Amateurs

Re: Mate in 11 position for amateurs.

Re: Mate in 11 position for Amateurs

Re: Mate in 11 position for Amateurs

Re: Mate in 11 position for Amateurs