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3 LD's from Maeda elementary

https://lifein19x19.com/viewtopic.php?t=3241

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3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 8:41 am
by cyclops
black to play, possibly ko
black to play, possibly ko
maeda1.JPG (134.72 KiB) Viewed 11276 times

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 10:36 am
by Mnemonic
Last time I chickened out and skipped the harder problems. I'll try to do better this time.

#187
First I thought that black just plays at :b1:, but then white plays :w2: and black can only capture a dead shape. So the best I could do is get a ko where black takes first.
Click Here To Show Diagram Code
[go]$$Bc No good
$$------------------
$$ . . X O . 1 . |
$$ . O O X X O 2 |
$$ . . . O X O O |
$$ . . . O X X X |
$$ . . . O O O . |
$$ . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$Bc Ko for black
$$------------------
$$ . . X O 4 3 2 |
$$ . O O X X O 1 |
$$ . . . O X O O |
$$ . . . O X X X |
$$ . . . O O O . |
$$ . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$Bc 8 takes the ko
$$------------------
$$ . . X 7 6 5 O |
$$ . O O X X O . |
$$ . . . O X O O |
$$ . . . O X X X |
$$ . . . O O O 8 |
$$ . . . . . . . |[/go]
#188
this one seemed simple so I probably got it wrong :-?
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 3 O X O X . . .
$$ | . 1 2 O X . . .
$$ | . . . O X . X .
$$ | . . . . O . . .
$$ ------------------[/go]
#189
I first thought that :b1: would work, but after :w2: you have a must win ko for black. Not good :sad:
Click Here To Show Diagram Code
[go]$$Bc
$$ . . . . . . . . |
$$ . . . . . . . . |
$$ . . . . . . O . |
$$ . . . O O O . . |
$$ . . . O X X O O |
$$ . . . O X . X . |
$$ . O . O X O . X |
$$ . . . X . 1 2 . |
$$ ----------------[/go]
Click Here To Show Diagram Code
[go]$$Bc
$$ . . . . . . . . |
$$ . . . . . . . . |
$$ . . . . . . O . |
$$ . . . O O O . . |
$$ . . . O X X O O |
$$ . . . O X . X . |
$$ . O . O X O . X |
$$ . . . X 3 2 1 . |
$$ ----------------[/go]
After :w2: black has to play again in the corner, but I don't think it really matters where you play exactly. I think :b3: is best endgame wise.

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 10:43 am
by mw42
@Mnemonic
How to answer :w4: ? Your first move was correct.
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 3 O X O X . . .
$$ | . 1 2 O X . . .
$$ | . 4 . O X . X .
$$ | . . . . O . . .
$$ ------------------[/go]

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 10:59 am
by Mnemonic
#188 new try
Damn, didn't see that. I had considred that move, but only after white conected. :sad: Back to the drawing board. This is the only :b3: that makes sense to me and now it looks like a capturing race.
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | 5 X X . . . . .
$$ | X O X . . . . .
$$ | 7 O O X X . . .
$$ | 4 O 8 O X . . .
$$ | 2 X O O X . . .
$$ | 3 1 6 O X . X .
$$ | . . 9 . O . . .
$$ ------------------[/go]
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | 5 O O X X . . .
$$ | 3 O 6 O X . . .
$$ | . X O O X . . .
$$ | . 1 2 O X . X .
$$ | . 4 7 8 O 9 . .
$$ ------------------[/go]

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 11:29 am
by unkx80
To Mnemonic:
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | . X O O X . . .
$$ | . 1 . O X . X .
$$ | . . . . O . . .
$$ ------------------[/go]
How would you answer this :w2:?

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 11:57 am
by Sverre
I couldn't solve 188.
Click Here To Show Diagram Code
[go]$$ 187, 5@3 for ko
$$-------+
$$..XO432|
$$.OOXXO1|
$$...OXOO|
$$...OXXX|
$$...OOO.|
$$.......|[/go]
Click Here To Show Diagram Code
[go]$$ 189, no ko
$$......O.|
$$...OOO..|
$$...OXXOO|
$$...OX.X.|
$$.O.OXO.X|
$$...X..1.|
$$--------+[/go]

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 12:29 pm
by Mnemonic
unkx80 wrote:To Mnemonic:
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | . X O O X . . .
$$ | . 1 . O X . X .
$$ | . . . . O . . .
$$ ------------------[/go]
How would you answer this :w2:?
Arg. Not again. Of course the easiest problem is the hardest one. I don't think black can win the capturing race after the decent, but I'm having trouble coming up with any other move that works.

Ok, I've now tried ever other possible combination that comes to mind and I don't see anything :sad: Let's try the capturing race again.

Ok, how about this. 2 stage approach ko for black? (While editing diagrams I actually noticed, it's only a normal ko and white takes first :sad: :sad: )
Click Here To Show Diagram Code
[go]$$Bc 10 at 4
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O 8 O X . . .
$$ | 6 X O O X . . .
$$ | 9 1 3 O X . X .
$$ | . 5 4 7 O . . .
$$ ------------------[/go]
If this isn’t it I might as well just give up! I guess I really suck :oops:

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 1:40 pm
by mw42
@Mnemonic
In your diagram
Click Here To Show Diagram Code
[go]$$B
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O 8 O X . . .
$$ | 6 X O O X . . .
$$ | . 1 3 O X . X .
$$ | . 5 4 7 O 9 . .
$$ ------------------[/go]
Why not just capture and escape with :b9: ?

White can make a ko after your move (see MW's post).
Click Here To Show Diagram Code
[go]$$B
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | 4 X O O X . . .
$$ | . 1 3 O X . X .
$$ | . . . . O . . .
$$ ------------------[/go]
Black has a better move.

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 2:25 pm
by Mnemonic
Why not just capture and escape with :b9: ?
Because that would be too easy :roll:

Last try:
Click Here To Show Diagram Code
[go]$$B This?
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | 4 X O O X . . .
$$ | . 1 3 O X . X .
$$ | . . . . O 5 . .
$$ ------------------[/go]

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 2:49 pm
by Magicwand
Mnemonic wrote:
Why not just capture and escape with :b9: ?
Because that would be too easy :roll:

Last try:
Click Here To Show Diagram Code
[go]$$B This?
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | 4 X O O X . . .
$$ | . 1 3 O X . X .
$$ | . . . . O 5 . .
$$ ------------------[/go]
Click Here To Show Diagram Code
[go]$$B
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | . X O O X . . .
$$ | 6 1 3 O X . X .
$$ | . 4 5 . O . . .
$$ ------------------[/go]
this is ko?

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 3:05 pm
by mw42
Mnemonic wrote:
Why not just capture and escape with :b9: ?
Because that would be too easy :roll:

Last try:
Click Here To Show Diagram Code
[go]$$B This?
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | 4 X O O X . . .
$$ | . 1 3 O X . X .
$$ | . . . . O 5 . .
$$ ------------------[/go]
I believe MW's :w4: is better than mine.
Click Here To Show Diagram Code
[go]$$B Ko.
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | . X O O X . . .
$$ | . 1 3 O X . X .
$$ | . 4 6 . O 5 . .
$$ ------------------[/go]
Solution:
Click Here To Show Diagram Code
[go]$$B
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | . X O O X . . .
$$ | . 1 . O X . X .
$$ | . . 3 . O . . .
$$ ------------------[/go]

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 5:29 pm
by cyclops
hint about 188
mw's solution was my solution too. But it is wrong. If Sverre did not solve it, you better think twice.

Re: 3 LD's from Maeda elementary

Posted: Fri Feb 18, 2011 9:15 pm
by Magicwand
solution:
one i posted before is to show that it was not a solution.
bottom seems like a solution.
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | . X O O X . . .
$$ | . 1 . O X . X .
$$ | . . . . O 3 . .
$$ ------------------[/go]
edit:
sorry..
i see the flaw in my reasoning.
this should be correct.
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 2 O . O X . . .
$$ | . X O O X . . .
$$ | . 1 . O X . X .
$$ | . . 3 . O . . .
$$ ------------------[/go]

Re: 3 LD's from Maeda elementary

Posted: Sat Feb 19, 2011 12:08 am
by Bill Spight
OK, I'll bite.
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . X X . . . . .
$$ | X O X . . . . .
$$ | . O O X X . . .
$$ | 3 O X O X . . .
$$ | . 1 4 O X . . .
$$ | 5 2 . O X . X .
$$ | . . . . O . . .
$$ ------------------[/go]

Re: 3 LD's from Maeda elementary

Posted: Sat Feb 19, 2011 4:01 am
by cyclops
congratulations, bill!
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