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Subject: Re: Interesting KRP to KP game, for your program

Author: Roy Eassa

Date: 16:26:00 06/12/02

Go up one level in this thread


On June 12, 2002 at 19:04:54, Roy Eassa wrote:

>On June 12, 2002 at 18:37:30, Roy Eassa wrote:
>
>>On June 12, 2002 at 18:32:43, Roy Eassa wrote:
>>
>>>On June 12, 2002 at 18:26:05, Roy Eassa wrote:
>>>
>>>>On June 12, 2002 at 16:46:50, Ferdinand S. Mosca wrote:
>>>>
>>>>>[D]6R1/1p1r2p1/p3k1Pp/P2pP2K/2pP4/2P5/1P6/8 w - - 0 51
>>>>
>>>>
>>>>Fritz 7 does not see the rook sacrifice in a short amount of time.  Here's what
>>>>I think is the main line:
>>>>
>>>>1.Rxg7 Rxg7 2.Kxh6 Rg8 3.Kh7 Rb8 4.g7 Kf7 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 +-
>>>>
>>>>
>>>>Any program must see in advance that the resulting K&P endgame (see diagram
>>>>below) is won for White.
>>>>
>>>>[d] 6K1/1p6/p3k3/P2p4/2pP4/2P5/1P6/8 b - -
>>>
>>>
>>>1.Rxg7! Rxg7 2.Kxh6 Rg8
>>>
>>>   [2...Re7 3.g7 Kf7 4.Kh7 Re8 5.e6+ transposes]
>>>
>>>3.Kh7 Rb8 4.g7 Kf7 5.e6+ Kf6
>>>
>>>   [5...Kxe6 6.g8Q+ Rxg8 7.Kxg8 +-]
>>>
>>>6.g8Q Rxg8 7.Kxg8 Kxe6 8.Kg7 Ke7 9.Kg6 Ke6 10.Kg5 Ke7 11.Kf5 +-
>>
>>
>>Fritz 7, 1.2 GHz AMD, after 3.5+ minutes:
>>
>>1.Rf8 Re7 2.Kh4 Rd7 3.Ra8 Re7 4.Kh5 Rc7
>>  ±  (0.88)   Depth: 12/22   00:00:00  267kN
>>1.Rf8 Re7 2.Kh4 Rd7 3.Kg4 Re7 4.Kf4 Kd7 5.Kf5 Kc7 6.Rf7 Kd7 7.e6+ Ke8 8.Rxe7+
>>  ±  (0.75)   Depth: 13/24   00:00:00  408kN
>>1.Rf8 Re7 2.Kh4 Rd7 3.Kg4 Re7 4.Kh5
>>  ±  (0.75)   Depth: 14/24   00:00:01  657kN
>>1.Rf8 Re7 2.Rf1 Kd7 3.b3 cxb3 4.Rb1 Re6 5.Rxb3 Kc7 6.Rb2 b5 7.Rf2 Kc6 8.Rf7
>>  ±  (0.84)   Depth: 15/27   00:00:03  1543kN
>>1.Rf8 Re7 2.Rf1 Kd7 3.b3 cxb3 4.Rb1 Re6 5.Rxb3 Kc7 6.Rb2 b6 7.Rf2 Kd7 8.axb6
>>  ±  (0.94)   Depth: 16/27   00:00:04  2194kN
>>1.Rf8 Re7 2.Rf1 b6 3.axb6 Rb7 4.Rf7 Rxb6 5.Rxg7 Rxb2 6.Ra7 Rh2+ 7.Kg4 Rg2+ 8.Kf3
>>  ±  (0.75)   Depth: 17/31   00:00:10  5694kN
>>1.Re8+!
>>  ±  (0.78)   Depth: 17/31   00:00:12  6310kN
>>1.Re8+ Re7 2.Rd8 Rd7 3.Rh8
>>  ±  (0.78)   Depth: 18/32   00:00:15  8147kN
>>1.Re8+ Re7 2.Rd8 Rd7 3.Rh8
>>  ±  (0.78)   Depth: 19/34   00:00:23  12365kN
>>1.Rf8!
>>  ±  (0.81)   Depth: 19/34   00:00:26  13957kN
>>1.Rf8 Re7 2.Rf1 Rd7 3.Kg4 b6 4.Rf8 bxa5 5.Ra8 Rb7 6.Rxa6+ Ke7 7.Kf5 h5 8.Rxa5
>>  ±  (1.00)   Depth: 20/35   00:00:53  28847kN
>>1.Rf8 Re7 2.Rf1 Rd7 3.Kg4 Re7 4.b3 cxb3 5.Rb1 b5 6.axb6 Rb7 7.Rxb3 a5 8.Kh5
>>  ±  (1.16)   Depth: 21/38   00:02:46  89209kN
>
>
>Here's Fritz after 30 minutes, still clueless:
>
>1.Rf8 Re7 2.Kh4 Rd7 3.Ra8 Re7 4.Kh5 Rc7
>  ±  (0.88)   Depth: 12/22   00:00:00  267kN
>1.Rf8 Re7 2.Kh4 Rd7 3.Kg4 Re7 4.Kf4 Kd7 5.Kf5 Kc7 6.Rf7 Kd7 7.e6+ Ke8 8.Rxe7+
>  ±  (0.75)   Depth: 13/24   00:00:00  408kN
>1.Rf8 Re7 2.Kh4 Rd7 3.Kg4 Re7 4.Kh5
>  ±  (0.75)   Depth: 14/24   00:00:01  657kN
>1.Rf8 Re7 2.Rf1 Kd7 3.b3 cxb3 4.Rb1 Re6 5.Rxb3 Kc7 6.Rb2 b5 7.Rf2 Kc6 8.Rf7
>  ±  (0.84)   Depth: 15/27   00:00:03  1543kN
>1.Rf8 Re7 2.Rf1 Kd7 3.b3 cxb3 4.Rb1 Re6 5.Rxb3 Kc7 6.Rb2 b6 7.Rf2 Kd7 8.axb6
>  ±  (0.94)   Depth: 16/27   00:00:04  2194kN
>1.Rf8 Re7 2.Rf1 b6 3.axb6 Rb7 4.Rf7 Rxb6 5.Rxg7 Rxb2 6.Ra7 Rh2+ 7.Kg4 Rg2+ 8.Kf3
>  ±  (0.75)   Depth: 17/31   00:00:10  5694kN
>1.Re8+!
>  ±  (0.78)   Depth: 17/31   00:00:12  6310kN
>1.Re8+ Re7 2.Rd8 Rd7 3.Rh8
>  ±  (0.78)   Depth: 18/32   00:00:15  8147kN
>1.Re8+ Re7 2.Rd8 Rd7 3.Rh8
>  ±  (0.78)   Depth: 19/34   00:00:23  12365kN
>1.Rf8!
>  ±  (0.81)   Depth: 19/34   00:00:26  13957kN
>1.Rf8 Re7 2.Rf1 Rd7 3.Kg4 b6 4.Rf8 bxa5 5.Ra8 Rb7 6.Rxa6+ Ke7 7.Kf5 h5 8.Rxa5
>  ±  (1.00)   Depth: 20/35   00:00:53  28847kN
>1.Rf8 Re7 2.Rf1 Rd7 3.Kg4 Re7 4.b3 cxb3 5.Rb1 b5 6.axb6 Rb7 7.Rxb3 a5 8.Kh5
>  ±  (1.16)   Depth: 21/38   00:02:46  89209kN
>1.Rf8 Re7 2.Rf1 Rd7 3.Kg4 Rd8 4.b4 cxb3 5.Rb1 h5+ 6.Kg5 h4 7.Kxh4 Kf5 8.Rxb3
>  ±  (1.19)   Depth: 22/40   00:07:04  239771kN
>1.Rf8 Re7 2.Rf1 Rd7 3.Kg4 Ke7 4.b4 cxb3 5.Rb1 b6 6.axb6 Rb7 7.Rxb3 a5 8.Rb2
>  ±  (1.28)   Depth: 23/46   00:17:09  609964kN
>1.Rf8 Re7 2.Rf1 Rd7 3.Kg4 Re7 4.Rb1 b6 5.axb6 a5 6.b3 cxb3 7.Rxb3 Rb7 8.Kh5
>  ±  (1.25)   Depth: 24/46   00:25:00  883748kN



I played the first 3 ply manually (see diagram below) and STILL Fritz 7 does not
see the trouble black is in.  After 92 seconds, it fails low (seeing SOME
danger) but even after 20 minutes it hasn't added another ply or any resolution:

[d]8/1p4r1/p3k1PK/P2pP3/2pP4/2P5/1P6/8 b - - 0 2
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8
  µ  (-0.88)   Depth: 13/21   00:00:00  208kN
2...Rc7--
  ³  (-0.59)   Depth: 14/21   00:00:00  246kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7
  ³  (-0.50)   Depth: 14/21   00:00:00  287kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kf6 6.g8Q Rxg8 7.Kxg8 Kxe6 8.Kf8 Kf6 9.Ke8 Ke6
  ³  (-0.56)   Depth: 15/22   00:00:00  457kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7 8.Kg7 Ke6 9.Kg6 Ke7
  ³  (-0.38)   Depth: 16/25   00:00:01  733kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7 8.Kg7 Ke6 9.Kg6 Ke7
  ³  (-0.38)   Depth: 17/26   00:00:02  1170kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7 8.Kg7 Ke8 9.Kf6 Kd7
  =  (-0.25)   Depth: 18/27   00:00:03  2030kN
2...Rc7--
  =  (0.03)   Depth: 19/29   00:00:05  3355kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7 8.Kg7 Ke6 9.Kg8 Ke7
  =  (0.00)   Depth: 19/33   00:00:08  5279kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7 8.Kg7 Ke6 9.Kg8 Ke7
  =  (0.00)   Depth: 20/31   00:00:11  7472kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7 8.Kg7 Ke6 9.Kg8 Ke7
  =  (0.00)   Depth: 21/33   00:00:17  11233kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7 8.Kg7 Ke6 9.Kg8 Ke7
  =  (0.00)   Depth: 22/36   00:00:28  18152kN
2...Rc7 3.g7 Kf7 4.Kh7 Rc8 5.e6+ Kxe6 6.g8Q+ Rxg8 7.Kxg8 Ke7 8.Kg7
  =  (0.00)   Depth: 23/39   00:00:53  33974kN
2...Rc7--
  ²  (0.44)   Depth: 24/42   00:01:32  60006kN



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