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        riddles >> medium >> Chess Puzzle 2
        
(Message started by: ThudanBlunder on Dec 31st, 2009, 1:59am)
Title: Chess Puzzle 2
Post by ThudanBlunder on Dec 31st, 2009, 1:59am
Create a position where White has a lone king against the Black king and three pawns, it is Black to move, and the result is a draw. No doubled or tripled pawns are allowed.
Title: Re: Chess Puzzle 2
Post by Hippo on Dec 31st, 2009, 8:07am
[hide]
Ke3
ka8 pd3 pf3 ph6
seems to be solution
[/hide]

BTW: Thanks for remembering the Christmas Time :)
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Dec 31st, 2009, 12:14pm

Quote:
BTW: Thanks for remembering the Christmas Time

Yeah, they have some good problems.
But f2 followed by h5 and your goose is cooked!
Title: Re: Chess Puzzle 2
Post by Hippo on Dec 31st, 2009, 2:15pm

on 12/31/09 at 12:14:03, ThudanBlunder wrote:
Yeah, they have some good problems.
But f2 followed by h5 and your goose is cooked!


Oh yes, you are absolutely right ... so starting again :)
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 1st, 2010, 6:24am

on 12/31/09 at 14:15:49, Hippo wrote:
Oh yes, you are absolutely right ... so starting again :)

And today's puzzle by Noam Elkies (http://www.chessbase.com/puzzle/christmas2009/chr09-08.htm) also looks interesting.
Title: Re: Chess Puzzle 2
Post by Three Hands on Jan 2nd, 2010, 7:49am
How about [hide]Kg2 : Ka1, pf6, pg3, ph6[/hide]?
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 2nd, 2010, 9:22am

on 01/02/10 at 07:49:50, Three Hands wrote:
How about [hide]Kg2 : Ka1, pf6, pg3, ph6[/hide]?

Do you have a plan in mind? I don't see how the White king can stop the f and h pawns, even without the Black king supporting.
Title: Re: Chess Puzzle 2
Post by Three Hands on Jan 3rd, 2010, 8:15am
As a potential sequence of play:

[hide]... f5
Kxg3 h5
Kf4 h4
Kf3 - from here, either f4 leads to a fairly simple take and hunt down, or h3 leads to Kg3 and curtains for the pawns. [/hide]

Then again, I'm nowhere near a grandmaster, so I may well have missed the optimal play for black...
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 3rd, 2010, 8:33am

on 01/03/10 at 08:15:00, Three Hands wrote:
As a potential sequence of play:
... f5
Kxg3 h5
Kf4 h4
Kf3 - from here, either f4 leads to a fairly simple take and hunt down, or h3 leads to Kg3 and curtains for the pawns.

OK, Black needs his king, with which he wins easily.

I can see how one might stop K + 2p, but not K + 3p
eg. Kf1, kh1, ph2, pf3
Title: Re: Chess Puzzle 2
Post by Hippo on Jan 4th, 2010, 5:36am
I spent a lot of time on this one with no progress :).
What I could say is that white either takes in his first move or is stalemated (otherwise there is shorter solution).
Stalemate seems to me is impossible ... in that case white should take two pawns before the black king approaches or the pawns start supporting each other by promoting threat and this seems is impossible, too ...

The last pawn need not be taken, it is sufficient to get to the draw situation as for the a/h pawn. But rather being under the pawn as forcing the opponent to be under the pawn while taking remaining pawns is not promising at all.
Title: Re: Chess Puzzle 2
Post by JohanC on Jan 4th, 2010, 1:38pm
What's your opion about
white: [hide]Kb2[/hide]
black: [hide]Ka8 a6 b3 d4[/hide] ?
Title: Re: Chess Puzzle 2
Post by Three Hands on Jan 4th, 2010, 1:41pm

on 01/03/10 at 08:33:41, ThudanBlunder wrote:
OK, Black needs his king, with which he wins easily.

I can see how one might stop K + 2p, but not K + 3p
eg. Kf1, kh1, ph2, pf3


Main reason I removed the black king from the effective play area - as it takes 4 turns of dedicated movement from his start position before he can protect any of his pieces, the battle's already done before he can get in the action...

As soon as the black king can provide protection/support for a surviving pawn or two, white can only really hope for an error in black's play...
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 4th, 2010, 2:02pm

on 01/04/10 at 13:38:35, JohanC wrote:
What's your opion about
white: [hide]Kb2[/hide]
black: [hide]Ka8 a6 b3 d4[/hide] ?

Yes, I think you've cracked it, Johan! Well done!   8)
Title: Re: Chess Puzzle 2
Post by JohanC on Jan 4th, 2010, 2:24pm
It's funny that the black king would win if he started in the further away corner.
Title: Re: Chess Puzzle 2
Post by Hippo on Jan 4th, 2010, 2:30pm
I am missing something:
0. ... Kb7
1. Kxb3 Kb6
2. Kc4 Ka5
3. Kxd4 Kb4
... it seems to me black wins
Title: Re: Chess Puzzle 2
Post by JohanC on Jan 4th, 2010, 3:08pm

on 01/04/10 at 14:30:09, Hippo wrote:
I am missing something:
0. ... Kb7
1. Kxb3 Kb6
2. Kc4 Ka5
3. Kxd4 Kb4
... it seems to me black wins

Did you look at alternatives to 2. Kc4?
Maybe there are healthier moves?
These pawn endings can be really deceiving...
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 4th, 2010, 3:32pm

on 01/04/10 at 15:08:13, JohanC wrote:
Did you look at alternatives to 2. Kc4?
Maybe there are healthier moves?

Yes, such as 2. Kb4 first and only then 3. Kc4 (or 3. Kc3 if 2...d3)
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 4th, 2010, 4:07pm

on 01/04/10 at 14:24:22, JohanC wrote:
It's funny that the black king would win if he started in the further away corner.

Yeah, amazingly Black wins win his king starting on any square on the chessboard except a8!
Title: Re: Chess Puzzle 2
Post by JohanC on Jan 4th, 2010, 5:11pm

on 01/04/10 at 16:07:02, ThudanBlunder wrote:
Yeah, amazingly Black wins win his king starting on any square on the chessboard except a8!

And also if the black pawns were further away from their promotion field, black would win.
Such as having the a-pawn on a7 would allow a tempo. And having the d-pawn on d5 would allow the king to defend that pawn just in time.
Very subtle differences change the panaroma completely.
Title: Re: Chess Puzzle 2
Post by Hippo on Jan 4th, 2010, 11:47pm
Good job JohanC :)
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 5th, 2010, 1:37am
But I still can't figure out the main puzzle here (http://www.chessbase.com/puzzle/christmas2009/chr09-08.htm).
How can the order of the first three moves change anything?
And the White knights on a3 and b1 seem to deny any stalemate.
Any thoughts?
Title: Re: Chess Puzzle 2
Post by Hippo on Jan 6th, 2010, 1:07am
As I thing on it ... it seems to me that after black puts queen at g6 with Pf7, Kg8 and as there is no stalemate trick, white should go Kf8 to protect the pawn which allows black to step his king. After several repetitions (may be mirrored) the black king approaches f6. White can sacrify a knight in the process, but than black promotes his d3 pawn and mates with two queens while white has pawn and a knight to prevent the stalemate.

This initial position should be prevented. But with the Qd1+ black has time enough and to prevent the + white looses tempo so black has enough time again. May be white can allow black to have 2 queens, but in that time he should be able to move Qa8 mate. I don't see where white can gain the tempo.
Title: Re: Chess Puzzle 2
Post by JohanC on Jan 7th, 2010, 12:57pm

on 01/05/10 at 01:37:09, ThudanBlunder wrote:
But I still can't figure out the main puzzle here (http://www.chessbase.com/puzzle/christmas2009/chr09-08.htm).
How can the order of the first three moves change anything?
And the White knights on a3 and b1 seem to deny any stalemate.
Any thoughts?

After reading the clues on that page, my idea is quite simple:
White just does the only sensible moves: [hide]advancing his/her f pawn, protecting it with the king. Black brings out the queen. Unlike the situation without the Na3-c2, now the queen can oblige the white king to f8 and use this tempo to slowly let his king come to the rescue.
Now, this slowlyness is the clue: if played well, white can force 50 moves without moving a pawn, which is one of the chess rules permitting to demand a draw.[/hide]
The reason the order of the first few moves is important, is that white [hide]should start with moving the f-pawn and only move his king on the 3rd move, to maximize the time without moving a pawn.[/hide]
Although I didn't check all the details, this seems to be the only way for the explanation on that page to make sense.
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 7th, 2010, 7:37pm

on 01/07/10 at 12:57:14, JohanC wrote:
Although I didn't check all the details, this seems to be the only way for the explanation on that page to make sense.

[hide]
Yes, this has to be it. How cunning! Well done. Black can force the White king in front of his own pawn every five moves and then move his own king. But the Black king needs 11 moves to reach the 6th rank to help capture the pawn. If White pushes his pawn to f7 first and awaits the check, I think Black needs 7 more moves to force the king to f8 for the first time.
So after 1.f6 Qb3 (1...Qc2 is also playable)
2. f7 Qd1+
we have
9. Kf8 Ka4
and
14. Kf8 Kb3
and
19. Kf8 Kb2
and
24. Kf8 Kc1
and
29. Kf8 Kd1
and
34. Kf8 Ke1
and
39. Kf8 Kf2
and
44. Kf8 Kf3
and
49. Kf8 Kf4
and
54. Kf8 Kf5
and (if the  Black king is at e6)
55. Kg7 Qg6+
56. Kf8 Ke6
57. Ke8 Qxf7 and 55 moves have been played since 2. f7

Playing a different move order wastes only one move and so I don't see how one move order saves the day by the 50-move rule and another doesn't. There must be something else to it . Maybe my counting is out by a few? [/hide]
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 8th, 2010, 4:39am
Anyway, Johan and Hippo, what do you make of this last (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_medium;action=display;num=1262180978) puzzle.
I think the first move is 1. Rd7
It wins against the obvious 1...Bxd7, anyway.
2. cxd7 Rd8
3. f6 etc.

But Black can play 1...Re3 with apparant equality.
Title: Re: Chess Puzzle 2
Post by ThudanBlunder on Jan 9th, 2010, 8:21am

on 01/04/10 at 17:11:47, JohanC wrote:
And also if the black pawns were further away from their promotion field, black would win.
Such as having the a-pawn on a7 would allow a tempo. And having the d-pawn on d5 would allow the king to defend that pawn just in time.
Very subtle differences change the panaroma completely.

I thought your solution was unique but it also works with the White king on a3!
Title: Re: Chess Puzzle 2
Post by Hippo on Jan 9th, 2010, 12:57pm

on 01/08/10 at 04:39:05, ThudanBlunder wrote:
Anyway, Johan and Hippo, what do you make of this last (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_medium;action=display;num=1262180978) puzzle.
I think the first move is 1. Rd7
It wins against the obvious 1...Bxd7, anyway.
2. cxd7 Rd8
3. f6 etc.

But Black can play 1...Re3 with apparant equality.


1. Rd7 Re3
2. f6 Bxd7
3. Bxd7 looks good as well

1. Rd7 Re3
2. f6 Rxh3
3. Rd8 mate
... nice solution ThudanBlunder

... skipped to the original thread
Title: Re: Chess Puzzle 2
Post by JohanC on Jan 9th, 2010, 5:49pm

on 01/09/10 at 08:21:10, ThudanBlunder wrote:
I thought your solution was unique but it also works with the White king on a3!

He, that's interesting. Although the play is very similar, it gives black even more freedom.
So, the chessbase challenge could be stricter: "no double or tirpple pawns and without the white king blocking a pawn".
Nice !
Title: Re: Chess Puzzle 2
Post by Hippo on Jan 10th, 2010, 12:26am

on 01/09/10 at 17:49:43, JohanC wrote:
So, the chessbase challenge could be stricter: "no double or tirpple pawns and without the white king blocking a pawn".
Nice !


Yes, but that would avoid the stalemate branch much faster so it would become easier.


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