Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: One mate to solve.

Author: leonid

Date: 14:18:51 02/26/02

Go up one level in this thread


On February 26, 2002 at 08:04:56, Heiner Marxen wrote:

>On February 25, 2002 at 12:43:33, leonid wrote:
>
>>On February 25, 2002 at 10:47:42, Heiner Marxen wrote:
>>
>>>On February 23, 2002 at 19:29:04, leonid wrote:
>>>
>>>>[D]5B2/pRNRQN2/p2qqrkr/K2p3p/P2q3n/P2bbnnq/PPQPNN2/5B2 w - -
>>>>
>>>>Please indicate your result.
>>>>
>>>>Thanks,
>>>>Leonid.
>>>
>>>Chest confirms that there is no mate-in-10.  Hence, the already found
>>>solutions in 11 moves are shortest possible.  I'll followup, if depth==11
>>>is completed...
>>
>>Thanks, Heiner!
>>
>>Your help is all the time valuable. This positions look like very easy and with
>>more, or less normal branching factor up to depth 10. At 10 it jump
>>dramatically. At least, it is true for my program. If mine looked 9 moves only
>>in 23 min. and had previous branching 6.65, it not responded for 10 moves even
>>after 8 hours. This signify that branching factor jumped more that two times.
>>
>>Cheers,
>>Leonid.
>
>Hi Leonid,
>
>Chest finds a unique key move for depth 11 (Athlon 1500+, 2.7 hours, 128MB hash)
>
>PV: Nh8+ Kf5 Bxh3+ Qg4 Qxd3+ Ne4 Nxe6 Bxd2+ b4 Bxb4+ Rxb4 Rxe6 Qf7+ Ref6 Rxd6
>Ng2 Rxd5+ Ne5 Rxe5+ Kxe5 Qfd5#
>
>Here is my timing info:
>#  4      0.03s                 3kN [  5.34]  1.04        459-         0
>#  5      0.17s [  5.67]       13kN [  4.27]  1.20       2522-         0
>#  6      0.70s [  4.12]       53kN [  3.95]  1.64      11254-         0
>#  7      2.63s [  3.76]      216kN [  4.10]  2.22      45584-         0
>#  8     13.78s [  5.24]     1468kN [  6.79]  2.56     249668-         0
>#  9    107.31s [  7.79]    15276kN [ 10.41]  2.59    1704722-      6749
># 10   1318.46s [ 12.29]   187860kN [ 12.30]  2.64   20453322-  17254089
># 11   9864.46s [  7.48]  1420383kN [  7.56]  2.70  151896018- 148696785
>
>So, it does jump with its EBF, but not as dramatically as for you.
>In the rest of my statistics I also do not see anything unusual or dramatic.
>Dunno, what kind of effect you are experiencing, sorry.

Hi, Heiner,

I don't know exactly how much my strange jumping in branching factor was really
for this position, since I had no patience to see all 10 moves deep. The last
time I put my computer to work at night and 8 hours later I disconnected it.
Then branching factor should be already around 22. Big surprise after previous
7.

For depth that I look, it was:

Moves        Time            Branching factor         NPS

4            0.219 sec                                49k
                             4.75
5            1.043 sec                                43k
                             4.89
6            5.38 sec                                 43k
                             4.4
7            22.5 sec                                 50k
                             9.01
8            3 min 24 sec                             77k
                             6.65
9            22 min 44 sec                            111k

I will try to put this position once again this Friday for 10 moves. I do go to
work in the morning, so I expect that computer could work entire night and up to
midday. I hope that nobody will use it at my absence. I am curious to see how
much time this position take. I do remember other very strange, probably much
more impressive position where branching factor went even to 115.

Conditions are usual. Celeron 600Mhz. No hash.

Cheers,
Leonid.


>Cheers,
>Heiner



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.