Author: leonid
Date: 03:39:02 05/06/01
Go up one level in this thread
On May 05, 2001 at 20:12:25, Heiner Marxen wrote:
>On May 05, 2001 at 18:41:22, Paul wrote:
>
>>On May 05, 2001 at 17:47:38, Heiner Marxen wrote:
>>
>>>On May 05, 2001 at 12:41:18, Paul wrote:
>>>
>>>>On May 05, 2001 at 11:55:58, leonid wrote:
>>>>
>>>>>Hello!
>>>>>
>>>>>If you would like to solve very easy mate, you can do this by solving one
>>>>>position from two, or both.
>>>>>
>>>>>[D]qk1r4/bpp1R1p1/pB1pnp2/N1Nb3p/2P1P3/QRnP2PB/5PK1/1r6 w - -
>>>>
>>>>Hi Leonid,
>>>>
>>>>this one is instantly solved by Pretz as a mate in 9:
>>>>
>>>>00:00 WM9 07 Nc6+ Bxc6 Nxa6+ bxa6 Bxc7+ Kc8 Qxa6+ Qb7 Bxe6+ Rd7 Bxd7+ Kxc7 Bxc6+
>>>>Kc8 Qxb7+ Kd8 Re8#
>>>
>>>As always, Pretz is faster than Chest. As often, Pretz in fact finds the
>>>shortest possible mate. I'm impressed, really!
>>
>>You are too kind, monsieur! But I have to say that in the last weeks Chest has
>>been faster than Pretz a number of times ... Sie sind zu Bescheiden, Herr Heiner
>>... Chest ist absolut unglaublich :)
>
>Many thanks for your kind words! Bescheidenheit ist eine Zier :-)
>
>>And I don't know why, but I like solving mates, combinations, puzzles, Rubik's
>>cubes (rediscovered one in my closet last week, it's a miracle thingy, really),
>>etc ... brains are strange entities, aren't they! Well ... mine is anyway ... ;)
>
>Yes, I also like puzzles of that kind where logic helps. I just solved
>some levels of sokoban. To those who don't share this hobby it often appears
>to be quite strange... it does not serve any obvious purpose... well,
>I just like to _solve_ puzzles, and enjoy the creative thinking involved.
>
>
>>>1.Nc6+ is the only key for mate in 9. Without duals this is a complete
>>>solution tree:
>>>
>>> Nc6+ Bxc6 Nxa6+ bxa6 Bxc7+ Kc8 Qxa6+ Qb7 Bxe6+ Rd7 Bxd7+ Kxc7 Bxc6+ Kc8 Bxb7+
>>>=*= Qxd6#
>>> Kd8 Re8+
>>>Kc7 Qxb7#
>>> Kb8 Qxb7#
>>> Bxd7 Qxb7#
>>> Bd7 Qxb7#
>>> Bb7 Bxe6+ Rd7 Bxd7+ Kxc7 Be6+ =*= Qxd6#
>>> Kc8 Rxc7#
>>> bxc6 Bxc7+ Kc8 Qxa6+ Qb7 Qxb7#
>>> Kc8 Rxc7#
>>>
>>>Took 48.1 minutes on K7/600 with 350 MB, so it wasn't exactly "easy" for Chest.
>>>
>>>>>[D]3k4/b2r4/4q3/2q3n1/1nnNbqnN/1Q1qpNBQ/r1BPQPp1/qNQRKR1N b - -
>>>>
>>>>And this one took a while longer as usual with your creations :), mate in 8:
>>>>
>>>>01:22 BM8 07 exf2+ Nxf2 Qaxd4 Bxd3 Qxf2+ Bxf2 Qxf2+ Rxf2 Bxf2+ Qxf2 Bxd3+ Qe3
>>>>g1=Q+ Nxg1 Qf2#
>>>>
>>>>Greetings,
>>>>Paul
>>>
>>>Oh yes, this one is harder. Up to now I know that there is no mate in 6
>>>(471 secs), and the effective branching factor appears to be above 20.
>>>Therefore I estimate well over 2 days for the mate in 8 to complete.
>>>I think I will let him do it. OTOH, within these two days Leonid will
>>>come up with at least two more of these ;-) Such is life.
>>
>>Wow ... this is unexpected! Tells you how much I know about matesolving.
>
>Hey, wait a second... while I write this answer, Chest comes up with a mate
>in 7! Sorry Paul, that is unexpected for me, too. Here we go:
>There are two key moves: exf2+ and Qaxd4 (the first two moves of your PV).
>My PVs (with some more variants) look like:
Thanks, Heiner! Very appreciated. I will try to solve this position later in 7.
Was not even sure if mine will have enough time to do this. Had very bad
branching factor for this one. Just to give you an idea:
3 moves - 0.1 sec
branching factor - 66
4 moves - 6.59 sec
- 38.6
5 moves - 4 min 14 sec
And this is where and why I stopped searching by brute froce the last time.
Cheers,
Leonid.
>exf2+ Bxf2 Qaxd4 Be3 Nxc2+ Qbxc2 Qxe2+ Kxe2 Qfxe3+ dxe3 Qxe3+ Qxe3 Qxe3#
> Nxf2 Qaxd4 Bxd3 Bxd3 Ne5 Qfxf2+ Bxf2 Qxf2+ Qxf2 Qxf2+ Rxf2 Bxf2#
> Rxf2 Qaxd4 Bxd3 gxh1Q+ Qhf1 Qxf2+ Bxf2 Qxf2+ Qxf2 Bxd3+ Ne5 Bxf2#
> Qxf2 Qcxd4 Qhxg2 Qxf2+ Qxf2 Bxf3+ Qe3 Qfxe3+ dxe3 Qe2#
>Qaxd4 Bxd3 exf2+ Bxf2 Qxf2+ Nxf2 Bxd3 Nd4 Qxe2+ Nxe2 Qfxf2+ Rxf2 Qxf2#
> Qbxd3 exf2+ Bxf2 Qxf2+ Nxf2 Bxd3 Nd4 Qxe2+ Nxe2 Qfxf2+ Rxf2 Qxf2#
> dxe3 Nxf3+ Nxf3 Qxe2+ Kxe2 Qxf3+ Ke1 Qdxe3+ fxe3 Qxf1#
> -*- Qcxe3+ Qxe3 Nxc2#
>
>Took 2.3 hours on K7/600 with 350MB hash.
>
>
>> And no,
>>this was one of Leonid's last problems, he's collected enough statistical data
>>over the last months, I think he's nearly finished. ;)
>
>Haha, you are joking ;-)
>OTOH, he must have quite an interesting collection by now. At some time,
>he should offer us the complete collection: "Easy and very easy mates" ;-)
>
>And then he starts his new collection "Not so easy mates" ... <shudder>.
>
>>>Groetjes,
>>>Heiner
>>
>>Haha ... perfect ... it's a catchy phrase, isn't it?
>
>Yes, exactly! I always wondered upon a good reply to it, and this time I
>got you!
>
>> And if you also pronounced
>>it, you're throat must be cleared now! ;) Always wondered how Dutch sounds to
>>"foreigners", but alas, I'll never know :(
>
>I'm from northern Germany, and do understand most of "Platt", which is not
>_that_ different... well there are some similarities. Some years ago I
>spent 3 days in Utrecht, visiting another puzzle fan (Andreas Gammel),
>so I have heard some Dutch myself. I dare to imagine the pronunciation
>of "Groetjes" (Chhhröitjes)... does that come close?
>
>>Venlig Hilsen,
>>:Paul
>
>Now you got me.. my Dutch/German is just not handy :-( I'll look it up.
>
>Herzliche Grüße aus Berlin,
>Heiner
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