Simple test positions

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Henk
Posts: 6556
Joined: Mon May 27, 2013 8:31 am

Simple test positions

Post by Henk » Fri Oct 16, 2020 7:37 am

Don't know why I come up with this position.

[d] 8/8/3k1p2/4p3/4P3/3K4/8/8 w - - 0 1

Already know that Skipper can't play endgames

Code: Select all

exclude: none best +tail                                          
dep	score	nodes	time	(not shown:  tbhits	knps	seldep)
 10	 -2.02 	5.15M  	1:22.27	d3c3  d6e6  c3c2  f6f5  c2d3  f5f4  d3e2  e6d6  e2f3  d6c5 
  9	 -2.02 	2.71M  	0:43.16	d3c3  d6e6  c3c2  f6f5  c2d3  f5f4  d3e2  e6d6  e2d3 
  8	 -1.07 	508965	0:08.29	d3c3  d6e6  c3b2  e6f7  b2b1  f7g6  b1a1  f6f5  e4f5  g6f5 
  7	 -1.07 	183499	0:02.97	d3c3  d6e6  c3b2  f6f5  e4f5  e6f5  b2a1 
  6	 -1.08 	69171  	0:01.23	d3c3  d6e6  c3b2  f6f5  e4f5  e6f5 
  5	 -1.08 	26230  	0:00.58	d3c3  d6e6  c3b2  f6f5  e4f5  e6f5 
  4	 -1.08 	8972 	0:00.32	d3c3  d6e6  c3b2  f6f5  e4f5  e6f5 
  3	 -1.05 	886 	0:00.19	d3c3  d6c5  c3d3 
  2	 -1.05 	234	0:00.18	d3c3  d6c5 
  1	 -1.05 	10	0:00.13	d3c3 
  

Sven
Posts: 3883
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Re: Simple test positions

Post by Sven » Fri Oct 16, 2020 4:20 pm

Should be easy with a good TT
Sven Schüle (engine author: Jumbo, KnockOut, Surprise)

Joost Buijs
Posts: 1176
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Location: Almere, The Netherlands

Re: Simple test positions

Post by Joost Buijs » Fri Oct 16, 2020 5:17 pm

The slow speed doesn't help either, 62 knps seems a bit slow for a simple position like this. Is the engine running on a RPI-1 or does it run with debug code?

zenpawn
Posts: 335
Joined: Sat Aug 06, 2016 6:31 pm
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Re: Simple test positions

Post by zenpawn » Sat Oct 17, 2020 12:13 pm

Henk wrote:
Fri Oct 16, 2020 7:37 am
Don't know why I come up with this position.
LOL. For those who don't know and/or future readers, this is from the end of Firouzja-Carlsen, Norway Chess 2020. Firouzja blundered with Kc3?? and resigned after ...Kc5. The move Kd2, taking distant opposition, is still a draw.
Erin Dame
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hgm
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Re: Simple test positions

Post by hgm » Sat Oct 17, 2020 12:53 pm

And it isn't just nps; there seems to be something horribly wrong with time-to-depth (or nodes-to-depth) as well. Fairy-Max needs only ~24K nodes (and consequently 0.01 sec) to reach depth 10, and it already switches to Kd2 there:

Code: Select all

dep	score	nodes	time	(not shown:  tbhits	knps	seldep)
 17	 -1.56 	333282	0:00.14	1. Kd2 Ke6 2. Ke3 f5 3. Kf3 Kf6 4. Ke3 fxe4 5. Kxe4 Ke6 6. Ke3 Kf5 
 16	 -1.61 	189677	0:00.07	1. Kd2 Ke6 2. Ke3 f5 3. Kf3 fxe4 4. Kxe4 Kd6 5. Kf3 Kd5 6. Ke3 e4 7. Kf4 Kd4 8. Kf5 e3 
 15	 -1.11 	124800	0:00.06	1. Kd2 Ke6 2. Ke3 f5 3. Kf3 fxe4 4. Kxe4 Kd6 5. Kf3 Kd5 6. Ke3 e4 7. Kf4 Kd4 8. Kf5 
 14	 -1.14 	96672  	0:00.04	1. Kd2 Ke6 2. Ke3 f5 3. Kf3 fxe4 4. Kxe4 Kd6 5. Kf3 Kd5 6. Ke3 e4 7. Kf4 
 13	 -1.13 	68330  	0:00.03	1. Kd2 Ke6 2. Ke3 f5 3. Kf3 f4 4. Kg4 Kf6 5. Kf3 Kg5 6. Ke2 Kg4 7. Kd3 
 12	 -0.74 	50436  	0:00.03	1. Kd2 Ke6 2. Ke3 f5 3. exf5 Kxf5 4. Kf3 
 11	 -1.05 	29255  	0:00.01	1. Kd2 Ke6 2. Ke2 f5 3. exf5 Kxf5 4. Ke3 e4 5. Kd4 
 10	 -0.95 	24360  	0:00.01	1. Kd2 Ke6 2. Ke3 f5 3. exf5 Kxf5 4. Kf3 
 10	 -0.96 	21975  	0:00.01	1. Ke3 Ke6 2. Ke2 f5 3. exf5 Kxf5 4. Kf3 e4 5. Ke3 Ke5 
 10	 -1.02 	19543  	0:00.01	1. Kc3 Ke6 2. Kb4 f5 3. exf5 Kxf5 4. Kc5 e4 5. Kd4 Kf4 
  9	 -0.75 	15921  	0:00.00	1. Kc3 Ke6 2. Kb4 f5 3. exf5 Kxf5 4. Kc5 e4 5. Kd5 
  9	 -0.81 	13147  	0:00.00	1. Ke3 Ke6 2. Ke2 f5 3. exf5 Kxf5 4. Kf3 e4 5. Kg3 
  9	 -0.94 	9212    	0:00.00	1. Kc2 Ke6 2. Kd2 f5 3. exf5 Kxf5 4. Ke3 e4 5. Kd4 
  8	 -0.75 	6202    	0:00.00	1. Kc2 Ke6 2. Kd2 f5 3. exf5 Kxf5 4. Ke3 e4 
  7	 -0.72 	4725    	0:00.00	1. Kc2 Ke6 2. Kc1 Ke7 3. Kd1 
  7	 -0.78 	3416    	0:00.00	1. Kc4 Ke6 2. Kc5 f5 3. exf5 Kxf5 4. Kd5 
  6	 -0.72 	2287    	0:00.00	1. Kc4 
  6	 -0.73 	1999    	0:00.00	1. Kc4 Ke6 2. Kc3 Kf7 3. Kd3 Kg6 
  5	 -0.69 	1281    	0:00.00	1. Kc4 Ke6 2. Kc3 
  5	 -0.70 	1027    	0:00.00	1. Kd2 Ke6 2. Kc3 f5 3. exf5 
  4	 -0.69 	387      	0:00.00	1. Kd2 Ke6 2. Kc3 f5 3. exf5 Kxf5 
  4	 -0.77 	274      	0:00.00	1. Ke2 Ke6 2. Kf3 f5 3. exf5 Kxf5 
  3	 -0.62 	123      	0:00.00	1. Ke2 Ke6 2. Ke3 
  2	 -0.63 	22        	0:00.00	1. Ke2 Ke6 
  1	 -0.62 	11        	0:00.00	1. Ke2 
Now one of course cannot be sure whether it did that because it saw the other moves were losing, or just accidentally because it slightly preferred it. So I also analyzed the position after the losing Kc3:

Code: Select all

	mover viewpoint		fewer / Multi-PV margin = 0 / more
exclude: none best +tail                                          
dep	score	nodes	time	(not shown:  tbhits	knps	seldep)
 28	+8.81 	7.73M  	0:03.54	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Kf2 Kd2 6. Kf3 Kd3 7. Kf2 Kxe4 8. Kg3 Kf5 9. Kf2 
 27	+8.75 	5.63M  	0:02.48	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kf2 Kxe4 8. Kg3 Kd3 9. Kg4 e4 10. Kf5 e3 11. Kxf6 e2 12. Kf5 e1=Q 13. Kf4 Kc3 14. Kg5 Kd4 
 26	+3.89 	2.69M  	0:01.18	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kf2 Kxe4 8. Ke2 f5 9. Kf2 f4 10. Ke2 f3 11. Kf2 Kf4 12. Kf1 Kg3 13. Kg1 e4 
 25	+3.95 	1.95M  	0:00.85	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Kf2 Kd4 6. Kf3 Kd3 7. Kf2 Kxe4 8. Ke2 
 24	+3.15 	919023	0:00.40	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kf2 Kxe4 8. Kg2 f5 9. Kh2 f4 10. Kh1 f3 11. Kg1 Ke3 12. Kh1 f2 13. Kh2 
 23	+3.12 	717467	0:00.31	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kg3 Kxe4 8. Kg4 f5 9. Kg3 f4 10. Kh3 f3 11. Kh2 f2 12. Kg2 Ke3 
 22	+2.93 	532600	0:00.23	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kg2 Kxe4 8. Kh2 
 21	+2.44 	400512	0:00.17	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kg3 Ke3 8. Kh3 Kf3 9. Kh2 Kxe4 
 20	+2.42 	318638	0:00.14	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Kf2 Kd4 6. Kf3 Kd3 7. Kg4 Kxe4 8. Kh5 f5 9. Kg6 f4 10. Kf7 f3 11. Kg7 
 19	+2.36 	243073	0:00.10	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kg3 Kxe4 8. Kg4 f5 9. Kg5 f4 10. Kf6 f3 
 18	+1.75 	169474	0:00.07	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Kf2 Kd4 6. Kf3 Kd3 7. Kg3 Kxe4 8. Kh2 f5 9. Kh3 
 17	+1.65 	128416	0:00.04	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kg3 Kxe4 8. Kh4 f5 9. Kg5 f4 
 16	+1.65 	99650  	0:00.04	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kg3 Kxe4 8. Kh3 f5 9. Kh2 
 15	+1.60 	82172  	0:00.03	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kg3 Kxe4 8. Kh4 f5 
 14	+1.49 	68364  	0:00.01	Kc5 2. Kd3 Kb4 3. Kd2 Kc4 4. Ke3 Kc3 5. Ke2 Kd4 6. Kf3 Kd3 7. Kg3 Kxe4 8. Kh3 
 14	+0.95 	57480  	0:00.01	Ke6 2. Kd3 f5 3. Ke3 f4 4. Kf3 Kd6 5. Kf2 Kc5 6. Kg2 Kc4 7. Kf2 Kd4 8. Kf3 
 13	+1.03 	33751  	0:00.01	Ke6 2. Kc4 f5 3. Kd3 fxe4 4. Kxe4 Kd6 5. Kd3 Kd5 6. Ke3 e4 7. Kf4 Kd4 
 12	+1.03 	25429  	0:00.01	Ke6 2. Kc4 f5 3. Kd3 fxe4 4. Kxe4 Kd6 5. Kd3 Kd5 6. Ke3 e4 7. Kf4 
 11	+1.04 	17977  	0:00.00	Ke6 2. Kc4 f5 3. Kd3 fxe4 4. Kxe4 Kd6 5. Kd3 Kd5 6. Ke3 e4 
 10	+0.83 	8542    	0:00.00	Ke6 2. Kc4 f5 3. exf5 Kxf5 4. Kd5 e4 5. Kd4 Kf4 6. Kd5 
  9	+0.83 	5126    	0:00.00	Ke6 2. Kc4 f5 3. exf5 Kxf5 4. Kd5 e4 5. Kd4 Kf4 
  8	+0.83 	3506    	0:00.00	Ke6 2. Kc4 f5 3. exf5 Kxf5 4. Kd5 e4 5. Kd4 
  7	+0.83 	2231    	0:00.00	Ke6 2. Kc4 f5 3. exf5 Kxf5 4. Kd5 e4 
  6	+0.74 	1189    	0:00.00	Ke6 2. Kc4 f5 3. exf5 Kxf5 4. Kd5 
  5	+0.75 	604      	0:00.00	Ke6 2. Kd3 f5 3. exf5 Kxf5 
  4	+0.75 	217      	0:00.00	Ke6 2. Kd3 f5 3. exf5 
  3	+0.75 	125      	0:00.00	Ke6 2. Kd3 f5 3. exf5 Kxf5 
  2	+0.72 	10        	0:00.00	Ke6 2. Kd3 
  1	+0.75 	3          	0:00.00	Ke6 
From this it can be seen that it needs ~250K nodes to see there is additional material gain after 1. Kc3. (Score > 2. But for thinking in the original position it would of course also spend some effort on moves other than 1. Kc3). It needs 2.5 sec to see the promotion.

It would be interesting to see what Skipper thinks in the position after1. Kc3.
Get rid of the shit: vote for SHID!

Henk
Posts: 6556
Joined: Mon May 27, 2013 8:31 am

Re: Simple test positions

Post by Henk » Sat Oct 17, 2020 1:18 pm

zenpawn wrote:
Sat Oct 17, 2020 12:13 pm
Henk wrote:
Fri Oct 16, 2020 7:37 am
Don't know why I come up with this position.
LOL. For those who don't know and/or future readers, this is from the end of Firouzja-Carlsen, Norway Chess 2020. Firouzja blundered with Kc3?? and resigned after ...Kc5. The move Kd2, taking distant opposition, is still a draw.
Yes for those who did not see it:

https://www.youtube.com/watch?v=9GjbRZcs6fA

Henk
Posts: 6556
Joined: Mon May 27, 2013 8:31 am

Re: Simple test positions

Post by Henk » Sat Oct 17, 2020 4:15 pm

Better. It did not use transposition table in main branch.

Code: Select all

dep	score	nodes	time	(not shown:  tbhits	knps	seldep)
 22	 -2.59 	14.8M  	3:50.75	d3d2  d6e6  d2e2  e6f7  e2d3  f7g6  d3e2  f6f5  e4f5  g6f5  e2d2 
 21	 -2.59 	13.0M  	3:22.50	d3d2  d6e6  d2e2  e6f7  e2d3  f7g6  d3e2  f6f5  e4f5  g6f5  e2d2 
 20	 -2.59 	10.8M  	2:47.73	d3d2  d6e6  d2e2  f6f5  e4f5  e6f5  e2d2  e5e4  d2e2  f5g5  e2e1  g5f6  e1f2  f6e5  f2e1  e4e3  e1f1  e5f4 
 19	 -2.44 	10.1M  	2:36.19	d3d2  d6e6  d2e2  e6e7  e2f3  e7d6  f3g3 
 19	 -2.59 	3.05M  	0:48.19	d3c2  f6f5  e4f5  e5e4  c2b2  d6e5  b2b1  e5f5  b1c2  f5e5  c2c1  e4e3  c1d1  e5d4  d1e2 
 18	 -2.44 	2.06M  	0:32.18	d3c2  d6e6  c2d2  e6f7  d2d1  f6f5  e4f5  e5e4  d1c1  f7g7  c1d1  g7f6  d1d2  f6f5  d2e3  f5e5  e3d2  e5d4 
 17	 -2.44 	1.60M  	0:25.17	d3c2  d6e6  c2d2  f6f5  d2e3  f5e4  e3e4  e6f6  e4e3  f6f5  e3f3  e5e4  f3e3  f5e5  e3d2  e5d4 
 17	 -3.09 	934478	0:14.74	d3c3  d6c5  c3d3  c5b4  d3d2  b4c4  d2e2  c4d4  e2f3  d4d3  f3g3  d3e4  g3g4  f6f5  g4g3  f5f4  g3f2 
 16	 -2.41 	237564	0:04.23	d3c3  d6c5  c3d3  c5b4  d3d2  b4c4  d2e2  c4d4  e2f3  d4d3  f3g3  d3e4  g3g4  e4d3  g4f5  e5e4  f5f6 
 15	 -2.19 	201620	0:03.57	d3c3  d6c5  c3d3  c5b4  d3d2  b4c4  d2e2  c4d4  e2f3  d4d3  f3g2  d3e4  g2h2  f6f5  h2h1 
 14	 -2.19 	135119	0:02.46	d3c3  d6c5  c3d3  c5b4  d3d2  b4c4  d2e2  c4d4  e2f3  d4d3  f3g2  d3e4  g2h1  f6f5 
 13	 -2.02 	88135  	0:01.66	d3c3  d6e6  c3d2  e6f7  d2c1  f7g6  c1c2  f6f5  c2d3  f5f4  d3e2  g6f6  e2d3 
 12	 -2.02 	60282  	0:01.18	d3c3  d6e6  c3d2  f6f5  d2e3  f5f4  e3e2  e6d6  e2f2  d6c5  f2f3  c5c4 
 11	 -2.03 	37684  	0:00.83	d3c3  d6e6  c3d2  f6f5  d2e3  f5f4  e3e2  e6d6  e2f3  d6c5  f3e2 
 10	 -2.02 	27874  	0:00.67	d3c3  d6e6  c3d2  f6f5  d2e3  f5f4  e3e2  e6d6  e2f3  d6c5 
  9	 -2.03 	20257  	0:00.53	d3c3  d6e6  c3d2  f6f5  d2e3  f5f4  e3f3  e6d6  f3e2 
  8	 -2.02 	9298    	0:00.36	d3c3  d6e6  c3d2  f6f5  d2e3  f5f4  e3f3  e6d6 
  7	 -1.07 	3253    	0:00.26	d3c3  d6e6  c3b2  f6f5  e4f5  e6f5  b2a1 
  6	 -1.08 	2520    	0:00.24	d3c3  d6e6  c3b2  f6f5  e4f5  e6f5 
  5	 -1.08 	640      	0:00.19	d3c3  d6e6  c3b2  f6f5  e4f5  e6f5 
  4	 -1.05 	154      	0:00.18	d3c3  d6c5  c3d3  c5c6 
  3	 -1.05 	68        	0:00.15	d3c3  d6c5  c3d3 
  2	 -1.05 	26        	0:00.15	d3c3  d6c5 
  1	 -1.05 	8          	0:00.12	d3c3 

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