Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: One test position

Author: Uri Blass

Date: 10:20:32 06/26/03

Go up one level in this thread


On June 26, 2003 at 12:48:36, Andrew Williams wrote:

>On June 26, 2003 at 11:18:26, Igor Gorelikov wrote:
>
>>One Test position
>>==================
>>
>>There is a section of everyday's puzzles on my site:
>>http://www.digichess.gr/infiniteloop/home.php
>>
>>All puzzles are taken from engine to engine games of Infinite Loop.
>>
>>Prior to publish a puzzle on my site I always offer Crafty 19.3 to solve it.
>>
>>I was amazed that today's puzzle was hard to solve even for Crafty so it
>>can be a good test position for any chess engine.
>>
>>What Phalanx XXII (engine number 10 among free WB engines) plays here as
>>white (and find it at once)?
>>
>>[D] r1bq3r/ppp3pp/3k4/3p4/3nP1Q1/8/PP4PP/RN3RK1 w - - 0 17
>>
>>PS: Yace can find it after some time too.
>>
>>Best regards,
>>Igor Gorelikov
>
>PostModernist (Athlon 1200) likes e5+ after about 2.5 seconds and sticks with it
>for a long time. It's currently searching depth 14 after 31 minutes, and the
>score is rising above +1 for the first time:
>
> 8>  +0.00   00:00:01.29    124572   1.Qg3 Ke6 2.Qg4 Kd6 3.Qg3 Ke6 4.Qg4 Kd6
>                                     5.Qg3 Ke6 6.Qg4 Kd6 7.Qg3 Ke6 8.Qg4 Kd6
> 8b  +0.01   00:00:02.51    273552   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4
> 8<  +0.36   00:00:03.06    357675   1.e5
> 8=  +0.34   00:00:03.07    359990   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 c6 4.Qf4 Kc5
>                                     5.b4 Kb6 6.Nc3
> 9<  +0.34   00:00:08.25   1139143   1.e5
> 9>  +0.25   00:00:08.98   1287446   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 Rf8
>                                     5.Qb4 Kd7 6.Qxb7
> 9=  +0.26   00:00:09.17   1342746   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 Rf8
>                                     5.Qb4 Kd7 6.Qxb7
>10>  +0.26   00:00:09.98   1454792   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 Rf8
>                                     5.Rfe1 Ke7 6.Rad1
>10<  +0.82   00:00:28.91   4055771   1.e5
>10=  +0.75   00:00:31.10   4507277   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 Rf8
>                                     5.Ne4 Kc6 6.Rfc1 Kd7 7.Nc5
>11<  +0.75   00:01:23.76  11351577   1.e5
>11>  +0.61   00:01:47.63  15449058   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 c6
>                                     5.Ne4 Kc7 6.Qe5 Kb6 7.Qxe6 dxe4 8.Qxe4
>11=  +0.65   00:01:48.33  15571854   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 c6
>                                     5.Ne4 Kc7 6.Qe5 Kb6 7.Qxe6 dxe4 8.Qxe4
>12<  +0.65   00:04:48.80  41307350   1.e5
>12>  +0.45   00:07:08.63  64619637   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Re1 Kd7
>                                     5.Nc3 c6 6.Qg7 Qe7 7.Qe5 Qf7
>12=  +0.50   00:07:09.79  64831671   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Re1 Kd7
>                                     5.Nc3 c6 6.Qg7 Qe7 7.Qe5 Qf7
>13>  +0.50   00:07:47.04  69753705   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 c6
>                                     5.Ne4 Kc7 6.Nc5 Qd6 7.Qg7 Bd7 8.Nxd7 Qxd7
>                                     9.Rf7
>13<  +0.85   00:25:22.84 221484627   1.e5
>13=  +0.83   00:26:17.63 230022136   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 c6
>                                     5.Rae1 Re8 6.Qg7 Qc7 7.Qe5 Kd7
>14>  +0.83   00:29:35.61 254958737   1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 c6
>                                     5.Rae1 Re8 6.Qg7 Qc7 7.Ne4 dxe4 8.Rd1
>
>
>It's going to take a long time to complete depth 14, so here is PM's "analysis
>mode" output after 37 minutes:
>
>time:00:37:48:04
>depth=14 score=+125
>nodes=319377591 nps=140756
>[+125 <= +132 <= +100000]
>PV: 1.e5 Kxe5 2.Qxg7 Kd6 3.Qxd4 Be6 4.Nc3 c6 5.Rae1 Re8
>    6.Qg7 Qc7 7.Ne4 dxe4 8.Rd1
>
>This means that PM's MTD(f) search has established that the score is > +1.25 and
>is now checking to see if it's higher or lower than +1.32
>
>Cheers
>
>Andrew

Here is Fritz8's analysis
Fritz8 finds the right move but not the right score.

New game
r1bq3r/ppp3pp/3k4/3p4/3nP1Q1/8/PP4PP/RN3RK1 w - - 0 1

Analysis by Fritz 8:

1.e5+ Kxe5
  ±  (1.06)   Depth: 7/12   00:00:00  16kN
1.e5+ Kxe5 2.Qf4+
  ±  (1.06)   Depth: 8/12   00:00:00  16kN
1.e5+ Kxe5 2.Qf4+ Ke6 3.Qxd4 Rf8
  ±  (1.06)   Depth: 9/30   00:00:00  241kN
1.e5+ Kxe5 2.Qf4+ Ke6 3.Qxd4 Rf8 4.Nc3 Rxf1+ 5.Rxf1 Qg5 6.Nb5 Qe5
  ±  (0.94)   Depth: 10/33   00:00:05  1468kN
1.e5+--
  ²  (0.66)   Depth: 11/34   00:00:22  7223kN
1.e5+ Kxe5 2.Qxg7+
  ²  (0.66)   Depth: 11/35   00:00:25  8300kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c5 4.Rf6+ Be6 5.Qf4+ Kd7 6.Nc3 Rf8 7.Nxd5
  ²  (0.63)   Depth: 12/37   00:01:16  26073kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c5 4.Rf6+ Be6 5.Qf4+ Kd7 6.Nc3 Rf8 7.Nxd5 Rxf6
8.Nxf6+ Kc8 9.Re1
  ±  (0.72)   Depth: 13/40   00:04:52  100700kN

(Blass, Tel-Aviv 26.06.2003)

1...Kxe5 and 2...Kd6 are forced to avoid 2.xx or 3.xx scores against black.

Even after 3.Qxd4
Fritz8 needs time to find the big problem.

New game
r1bq3r/ppp4p/3k4/3p4/3Q4/8/PP4PP/RN3RK1 b - - 0 1

Analysis by Fritz 8:

3...c5 4.Rf6+ Be6 5.Qf4+ Kd7 6.Nd2 Rf8 7.Qa4+ Ke7 8.Rff1
  ²  (0.69)   Depth: 6/21   00:00:00  39kN
3...c5 4.Rf6+ Be6 5.Qf4+ Kd7 6.Nd2 Rf8 7.Qa4+ Ke7 8.Rff1
  ²  (0.69)   Depth: 7/18   00:00:00  58kN
3...c5 4.Rf6+ Be6 5.Qf4+ Kd7 6.Nc3 Rf8 7.Nxd5 Rxf6 8.Nxf6+ Kc8 9.Rc1 Qe7
  ²  (0.62)   Depth: 8/25   00:00:01  227kN
3...c5--
  ±  (0.91)   Depth: 9/30   00:00:03  756kN
3...c5 4.Qf4+ Kc6 5.Nc3 Be6 6.Rae1 Re8 7.Qh6 Qd6 8.Rf6
  ±  (0.94)   Depth: 9/32   00:00:04  1118kN
3...c5 4.Qf4+ Kc6 5.Qh6+ Kc7 6.Rf7+ Bd7 7.Nc3 Kc8 8.Nxd5 Re8 9.Qd6 b6 10.Raf1
  ±  (1.16)   Depth: 10/29   00:00:08  2434kN
3...c5 4.Qf4+ Kc6 5.Qh6+ Kc7 6.Rf7+ Bd7 7.Nc3 Kc8 8.Nxd5 Re8 9.Qd6 b6 10.Raf1
  ±  (1.16)   Depth: 11/34   00:00:19  6192kN
3...c5--
  +-  (1.44)   Depth: 12/35   00:00:34  11425kN
3...c5 4.Qf4+ Kc6
  +-  (1.44)   Depth: 12/48   00:01:17  27035kN
3...Be6!
  +-  (1.41)   Depth: 12/48   00:02:15  48715kN
3...Be6--
  +-  (1.69)   Depth: 13/35   00:02:57  63394kN
3...Be6 4.Nc3 c6 5.Ne4+ Kc7 6.Nc5 Re8 7.Qg7+ Re7 8.Nxe6+ Kd6 9.Nxd8 Rxg7 10.Nf7+
  +-  (1.97)   Depth: 13/54   00:05:19  114584kN
3...c5!
  +-  (1.94)   Depth: 13/54   00:05:50  126407kN
3...c5!
  +-  (1.78)   Depth: 13/54   00:06:09  133871kN
3...c5 4.Qf4+ Kc6 5.Qh6+ Kc7 6.Rf7+ Bd7 7.Nc3 Kc8 8.Nxd5 b6 9.Rd1
  +-  (1.69)   Depth: 13/54   00:06:46  147815kN

(Blass, Tel-Aviv 26.06.2003)

Movei has no problem to find the move e5+ and here is some analysis
I guess that it needs more time to find big score for white.

New game
r1bq3r/ppp3pp/3k4/3p4/3nP1Q1/8/PP4PP/RN3RK1 w - - 0 1

Analysis by movei00_8_077:

1.e5+ Kxe5 2.Re1+ Kd6 3.Qxd4
  =  (-0.04)   Depth: 1   00:00:00
1.e5+ Kxe5 2.Re1+ Kd6 3.Qxd4
  =  (-0.04)   Depth: 2   00:00:00
1.e5+ Kxe5 2.Re1+ Kd6 3.Qxd4
  =  (-0.04)   Depth: 2   00:00:00
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4
  ±  (1.12)   Depth: 3   00:00:00
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4
  ±  (1.12)   Depth: 3   00:00:00
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 Qg8
  =  (0.05)   Depth: 4   00:00:00
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 Qg8
  =  (0.05)   Depth: 4   00:00:00
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c5 4.Qf4+ Kc6 5.Nc3
  =  (-0.01)   Depth: 5   00:00:00
1.Qg3+
  =  (0.00)   Depth: 5   00:00:01
1.Qg3+ Ke6 2.Qg4+ Kd6
  =  (0.00)   Depth: 5   00:00:01
1.Qg3+ Ke6 2.Qg4+ Kd6
  =  (0.00)   Depth: 5   00:00:01
1.Qg3+ Ke6 2.Qg4+ Kd6
  =  (0.00)   Depth: 6   00:00:01  225kN
1.e5+
  =  (0.01)   Depth: 6   00:00:01  258kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c5 4.Qf4+ Kc6 5.Qh6+ Kc7 6.Nc3
  =  (0.10)   Depth: 6   00:00:02  357kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c5 4.Qf4+ Kc6 5.Qh6+ Kc7 6.Nc3
  =  (0.10)   Depth: 6   00:00:02  378kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c6 4.Nd2 Re8 5.Rac1
  =  (0.03)   Depth: 7   00:00:04  762kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c6 4.Nd2 Re8 5.Rac1
  =  (0.03)   Depth: 7   00:00:07  1262kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 Qg8 4.Nd2 Kd7 5.Ne4 Kd8 6.Qf6+ Kd7
  =  (0.25)   Depth: 8   00:00:13  2243kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 Qg8 4.Nd2 Kd7 5.Ne4 Kd8 6.Qf6+ Kd7
  =  (0.25)   Depth: 8   00:00:19  3494kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c6 4.Nd2 Kc7 5.Qe5+ Kb6 6.a4 Ka6 7.b4
  ²  (0.51)   Depth: 9   00:00:38  6753kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 c6 4.Nd2 Kc7 5.Qe5+ Kb6 6.a4 Ka6 7.b4
  ²  (0.51)   Depth: 9   00:01:30  15879kN
1.e5+ Kxe5 2.Qxg7+ Kd6 3.Qxd4 Be6 4.Nc3 Kd7 5.Nxd5 Kc8 6.Ne7+ Kb8 7.Rad1 Qe8
  ²  (0.63)   Depth: 10   00:03:38  38274kN

(Blass, Tel-Aviv 26.06.2003)

Uri



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.