Author: Eduard Nemeth
Date: 14:32:23 06/02/01
Go up one level in this thread
On June 02, 2001 at 17:16:43, Heiner Marxen wrote:
>On June 02, 2001 at 15:07:49, Eduard Nemeth wrote:
>
>>On June 02, 2001 at 14:16:54, Heiner Marxen wrote:
>>
>>>On June 02, 2001 at 08:56:05, Eduard Nemeth wrote:
>>>
>>>>On June 02, 2001 at 07:44:10, leonid wrote:
>>>>
>>>>>Hi!
>>>>>
>>>>>If you want to solve one mate then try this:
>>>>>
>>>>>[D]1rqkqr2/nPpqpPn1/QQqqqQQ1/Qbb1BBQ1/1N3N2/8/3Q4/R2K2R1 w - -
>>>>>
>>>>>Please indicate your result.
>>>>>
>>>>>Thanks,
>>>>>Leonid.
>>>>
>>>>Hello Leonid!
>>>>
>>>>I give this position to analysis Genius6 (MCS) on P600 with 32 MB hash.
>>>>
>>>>Analysis by Genius6:
>>>>
>>>>{Mate in 10 Moves after 5:14 minutes)
>>>>
>>>>deph 5/17 HV: Mate in 10: 1.fxe8Q Rxe8 2.Nxc6+ Bxc6 3.Nxe6 Nxe6 4.Qxc7
>>>>
>>>>Regards,
>>>>Eduard
>>>
>>>Hi Eduard,
>>>
>>>On my K7/600 with 350 MB hash Chest needs 28.8 minutes to find that 6 of the
>>>73 initial legal moves lead to a mate in 9, so this is one of the rare
>>>cases, where Genius does not give optimal results straightaway.
>>>Here are the PVs of Chest:
>>>
>>>Nxc6+ Bxc6 fxe8Q+ Nxe8 bxc8Q+ Rxc8 Nxe6+ Q7xe6 Qxe7+ Qxe7 Bxd6 Bf3+ Kc1
>>> Ba3+ Bxa3+ Bd5 Bxe7#
>>>
>>>Nxe6+ Nxe6 fxe8Q+ Rxe8 bxc8Q+ Nxc8 Nxc6+ Bxc6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8
>>> Nf8 Qxe8+ Kxe8 Qgxf8#
>>>
>>>bxc8Q+ Nxc8 fxe8Q+ Rxe8 Nxe6+ Nxe6 Nxc6+ Bxc6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8
>>> Nf8 Qxe8+ Kxe8 Qgxf8#
>>>
>>>bxc8R+ Nxc8 fxe8Q+ Rxe8 Nxe6+ Nxe6 Nxc6+ Bxc6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8
>>> Nf8 Qxe8+ Kxe8 Qgxf8#
>>>
>>>fxe8Q+ Nxe8 bxc8Q+ Rxc8 Nxe6+ Q7xe6 Nxc6+ Bxc6 Qxe7+ Qxe7 Bxd6 Bf3+ Kc1
>>> Ba3+ Bxa3+ Bd5 Bxe7#
>>>
>>>fxe8R+ Nxe8 bxc8Q+ Rxc8 Nxe6+ Q7xe6 Nxc6+ Bxc6 Qxe7+ Qxe7 Bxd6 Bf3+ Kc1
>>> Ba3+ Bxa3+ Bd5 Bxe7#
>>>
>>>The huge hash table contributes not more than a factor 2 (for speed).
>>>Otherwise this is a typical "Leonid": lots of checks, and nearly every move
>>>is a capture ;-)
>>>
>>>Cheers,
>>>Heiner
>>
>>Thanks Heiner!
>>
>>When black 1...Nxe8 play, than this is a mate in 9 moves - correctly!
>>But, black play 1...Rxe8, than this is a mate in 10 moves.
>>
>>Kind Regards,
>>Eduard
>
>Hello Eduard!
>
>You seem to imply that after 1.fxe8Q Rxe8 there does not exist a following
>mate in 8. If that were true, Chest would have a bug, because it implicitly
>stated so. After the above two plies Chest gives these 4 PVs:
>
>Nxc6+ Bxc6 bxc8Q+ Nxc8 Nxe6+ Nxe6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8 Nf8
>Qxe8+ Kxe8 Qgxf8#
>
>Nxe6+ Nxe6 bxc8Q+ Nxc8 Nxc6+ Bxc6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8 Nf8
>Qxe8+ Kxe8 Qgxf8#
>
>bxc8Q+ Nxc8 Nxe6+ Nxe6 Nxc6+ Bxc6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8 Nf8
>Qxe8+ Kxe8 Qgxf8#
>
>bxc8R+ Nxc8 Nxe6+ Nxe6 Nxc6+ Bxc6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8 Nf8
>Qxe8+ Kxe8 Qgxf8#
>
>You seem to expect the first variant, i.e. 2.Nxc6+ Bxc6
>Ok, after 1.fxe8Q Rxe8 2.Nxc6+ Bxc6 you expect a mate in 8 with 3.Nxe6+ Nxe6,
>whereas Chest states a mate in 7. Here Chest gives 3 key moves:
>
>Nxe6+ Nxe6 Bxd6 Bf3+ Ke1 Bf2+ Qbxf2 Bd5 Qxe8+ Kxe8 Qg8+ Nf8
>Qgxf8#
>
>bxc8Q+ Nxc8 Nxe6+ Nxe6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8 Nf8 Qxe8+ Kxe8
>Qgxf8#
>
>bxc8R+ Nxc8 Nxe6+ Nxe6 Qxc6 Bb6 Qxe8+ Qxe8 Qg8 Nf8 Qxe8+ Kxe8
>Qgxf8#
>
>So you expected the first variant, but deeper.
>Ok, now we have 1.fxe8Q Rxe8 2.Nxc6+ Bxc6 3.Nxe6 Nxe6, and you expect Qxc7
>to be a solution for a mate in 7, while Chest still thinks there is a
>mate in 6. It finds 7 key moves to force the mate in 6, but Qxc7 is not
>one of them. After this Chest states Qcxc7 cannot be followed up by a mate
>in 5, and from another posting of you I see that it is this move, which
>you expect. So you are right except for choosing 4.Qxc7.
>Stronger (shorter) are:
>
>Bxd6 Bf3+ Ke1 Bf2+ Qbxf2 Bd5 Qxe8+ Kxe8 Qg8+ Nf8 Qgxf8#
>Qbxc5 Ba4+ Rxa4 Nb5 Q6xb5 Nd4 bxc8Q+ Rxc8 Qfxd6 Nc6 Qxd7#
>Qxc6 Nxc6 bxc8Q+ Rxc8 Bxd6 Ba3 Bxc7+ Rxc7 Qa8+ Nb8 Qxb8#
>Qxe7+ Q7xe7 bxc8Q+ Nxc8 Qxc6 Rb1+ Rxb1 Qxd2+ Qaxd2+ Nd4 Bxc7#
>Qxe8+ Qxe8 Bxd6 Ba4+ Qxa4 Bxd6 Qxe7+ Qxe7 Qdxd6+ Qd7 Qxe7#
>bxc8Q+ Nxc8 Qxc6 Bb6 Qxe8+ Qxe8 Qg8 Nf8 Qxe8+ Kxe8 Qgxf8#
>
>Do you agree? Otherwise I'm very interested in refutations of the above
>lines, since that would imply a bug in my program :-(
>
>[ The lines above are just PVs, of course. A complete solution tree is
> nearly 2000 lines long, even without multiple white choices below the top,
> so I omit that here. You can get it by e-mail on request, of course. ]
>
>Best regards,
>Heiner
Hello Heiner!
Sorry, but I have a problem - my bad english! :-(
Könntest Du mir - nur den Text - auf deutsch übersetzen oder zumailen?
sonst kann ich nicct antworten, sorry.
Kind Regards,
Eduard
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