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Subject: Re: One very easy mate...

Author: leonid

Date: 08:21:05 05/19/01

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On May 19, 2001 at 10:26:58, Heiner Marxen wrote:

>On May 19, 2001 at 08:36:17, leonid wrote:
>
>>On May 18, 2001 at 22:03:13, Heiner Marxen wrote:
>>
>>>On May 17, 2001 at 13:50:30, leonid wrote:
>>>
>>>>Hi!
>>>>
>>>>If somebody would like very easy mate, then this veriation from this first is
>>>>exactly this.
>>>>
>>>>[D]qr3rqB/3k3B/N1qqq1NQ/Q1n1n2Q/1qQ1Qq1Q/2RNR2Q/Q2K3b/1q3q1b w - -
>>>>
>>>>Please indicate your result.
>>>>
>>>>Thanks,
>>>>Leonid.
>>>
>>>Mate in 8.  Two key moves.  On K7/600 with 350 MB hash Chest after 441.12 sec
>>>(7.4 min) mutters:
>>
>>Excellent! Mine by brute force reached first solution (not all) in 4 min 10 sec.
>>
>>>
>>>Nxc5+ Qbxc5 Nxe5+  Qfxe5 Q6xe6+ Qdxe6 Nxc5+  Kc8   Qhxe6+ Qcxe6 Qxe6+  Qexe6
>>>Qexe6+ Qxe6 Qxe6#
>>>
>>>Nxe5+ Qfxe5 Nxc5+  Qbxc5 Q6xe6+ Qdxe6 Nxc5+  Kc8   Qhxe6+ Qcxe6 Qxe6+  Qexe6
>>>Qexe6+ Qxe6 Qxe6#
>>>
>>>As often, symetric solutions to a (nearly) symetric problem.
>>>Timing info reveals that Chest does feel quite comfortly:
>>>
>>>depth  seconds
>>>#  3      0.02  0.96         72-         0
>>>#  4      0.24  1.12        667-         0
>>>#  5      2.05  1.28       6153-         0
>>>#  6     13.72  1.53      44092-         0
>>>#  7     79.46  2.02     265586-         0
>>>#  8    441.02  2.70    1524472-         9
>>
>>Here I am confused. What is your node/per/second for 8 moves?
>
>The above numbers were intended to show the effective branching factor.
>The "nodes" above are "generated hash table entries", not searched positions.
>Those can be seen (indirectly) from the numbers below.
>
>>Mine is 93k per second when it looked 8 moves deep and by brute force. I am so
>>exact in indication since search 7 moves deep, for instance, give different
>>number. It is 152k. NPS for 5 and 6 moves deep is also different. Strange but
>>true.
>>
>>Cheers,
>>Leonid.
>>
>>>
>>>             white      black      quotients
>>>mvx  8:         32         38  [ 32.000  1.188]         39
>>>mvx  7:        708        722  [ 18.632  1.020]         91
>>>mvx  6:       7324       8085  [ 10.144  1.104]        185
>>>mvx  5:      57939      69121  [  7.166  1.193]       1052        147
>>>mvx  4:     423641     537738  [  6.129  1.269]       5565        198
>>>mvx  3:    2906635    3507479  [  5.405  1.207]
>>>mvx  2:   14814509    2992977  [  4.224  0.202]
>>>mvx  1:     275837          0  [  0.092       ]
>
>Summing the above move numbers (every move makes a new position searched)
>I get 25602785 / 441.02 = 58054 N/s.

Aha! Very close to my numbers once again. Your went down a little bit because of
heavy use of hash.

Leonid.
>
>Heiner
>
>
>>>Also, black likes to deliver mate-in-1 to white:
>>>anti: 2529687 try, 1637033 lists [64.71%], 2376273 moves [93.94%], 1461034 succ
>>>[57.76%]
>>>
>>>Cheers,
>>>Heiner



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