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Dame filling for dummies #1

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Dame filling for dummies #1

Posted: Fri Sep 20, 2013 9:01 am
by Bill Spight
Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . O X . . . X X O . . . O O . |
$$ | . . . O O O X X X . X O . . O O X O X |
$$ | . . O . . . O O O X O O O O O X X X . |
$$ | . . O O O O X . O X . O X X X X . X . |
$$ | O O X O O X X X X X . O O X . X X O . |
$$ | . . X X O O . . O . . O X X O X O . O |
$$ | X X X X X X X X O . O O X X X O O O . |
$$ | O O O X O . X O X X X O O O X X O O . |
$$ | . O . O O . X O . . X O . O X X X O . |
$$ | O X O , O X X O . X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X . |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X , X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O . |
$$ ---------------------------------------[/go]


Where are the protective plays?

Does any one of them need to be played immediately?

Enjoy!

Re: Dame filling for dummies #1

Posted: Fri Sep 20, 2013 12:48 pm
by daal
At the risk of being seen purchasing this book:

Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . O X . . . X X O . . . O O . |
$$ | . . . O O O X X X . X O . . O O X O X |
$$ | . . O . . . O O O X O O O O O X X X . |
$$ | . . O O O O X . O X . O X X X X . X . |
$$ | O O X O O X X X X X . O O X . X X O . |
$$ | . . X X O O . . O . . O X X O X O . O |
$$ | X X X X X X X X O . O O X X X O O O . |
$$ | O O O X O . X Q X X X O O O X X O O . |
$$ | . O . O O . X Q . . X O . O X X X O . |
$$ | O X O , O X X Q . X X X O . O X O . O |
$$ | . . O O O O X Q Q X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X b |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X c X X O |
$$ | . . X X O O . O O X X O O X O X X O a |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O d |
$$ ---------------------------------------[/go]


As Black, I would play at "a" to prevent white from starting a ko at "b", since White has some ko threats, including a serious one to cut off the black group on the top. It is however utterly unnecessary, because even if w managed to cut off the bottom group at "c," it would still be alive because of a double ko at "a" and "d." Eventually Black will need to capture the marked group in the center, but it is not urgent.

Re: Dame filling for dummies #1

Posted: Fri Sep 20, 2013 1:19 pm
by illluck
I don't see the ko daal referred to. My thoughts:

Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . O X . . . X X O . . f O O . |
$$ | . . . O O O X X X d X O . . O O X O X |
$$ | . . O . . b O O O X O O O O O X X X g |
$$ | . a O O O O X . O X . O X X X X . X . |
$$ | O O X O O X X X X X . O O X . X X O e |
$$ | . . X X O O . . O . . O X X O X O . O |
$$ | X X X X X X X X O c O O X X X O O O . |
$$ | O O O X O . X O X X X O O O X X O O . |
$$ | . O . O O . X O . . X O . O X X X O . |
$$ | O X O , O X X O . X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X . |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X , X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O . |
$$ ---------------------------------------[/go]


The above are the protective moves I can see, of these, "d" should be played as soon as possible as otherwise black needs spend moves inside to capture white.

Re: Dame filling for dummies #1

Posted: Fri Sep 20, 2013 1:32 pm
by daal
illuck:

Here is the double ko I was referring to. Knowing me, it's probably irrelevant to the problem. Your answer makes more sense in any case.

Re: Dame filling for dummies #1

Posted: Fri Sep 20, 2013 1:37 pm
by skydyr
daal wrote:illuck:

Here is the double ko I was referring to. Knowing me, it's probably irrelevant to the problem.


Black still has two giant threats around K1, while I don't see any big ones for white.

Re: Dame filling for dummies #1

Posted: Fri Sep 20, 2013 1:40 pm
by illluck
daal wrote:illuck:

Here is the double ko I was referring to. Knowing me, it's probably irrelevant to the problem. Your answer makes more sense in any case.


Neat find! I didn't see that at all. But yeah, it doesn't look like it changes the status of the corner.

Re: Dame filling for dummies #1

Posted: Fri Sep 20, 2013 1:41 pm
by illluck
skydyr wrote:
daal wrote:illuck:

Here is the double ko I was referring to. Knowing me, it's probably irrelevant to the problem.


Black still has two giant threats around K1, while I don't see any big ones for white.


It's a double ko as far as I can see, which means there's no need for ko threats.

Re: Dame filling for dummies #1

Posted: Fri Sep 20, 2013 8:57 pm
by skydyr
illluck wrote:
It's a double ko as far as I can see, which means there's no need for ko threats.

I meant from the end of daal's line, once it resolved into a fairly direct ko for black and a ko with followup ko for white.

Re: Dame filling for dummies #1

Posted: Sat Sep 21, 2013 2:31 am
by HermanHiddema
In daal's line, at the end white can defend at T3 to make a real ko...

Re: Dame filling for dummies #1

Posted: Sat Sep 21, 2013 2:57 am
by Cassandra
HermanHiddema wrote:
In daal's line, at the end white can defend at T3 to make a real ko...

But there is a correct path for Black to get a Double-Ko in the lower right corner that White cannot win.

This means that Black does not need any Ko-threats.

Re: Dame filling for dummies #1

Posted: Sat Sep 21, 2013 4:39 am
by wineandgolover
Fun problem. Deserves more likes.

Thanks, Bill!

Re: Dame filling for dummies #1

Posted: Sat Sep 21, 2013 8:20 am
by Bill Spight
wineandgolover wrote:Fun problem. Deserves more likes.

Thanks, Bill!


Thank you for the endorsement. :) As I said to Uzziel, there is skill to filling dame. :D

Re: Dame filling for dummies #1

Posted: Sun Sep 22, 2013 6:39 pm
by TheBigH
Where did this problem come from? Is it based on a game, or was it composed?

Either way, cool problem. :)

Re: Dame filling for dummies #1

Posted: Sun Sep 22, 2013 8:00 pm
by Bill Spight
This problem comes from a game: Tamura (W) vs. Tsuchiya in 1897. Tamura later became Honinbo Shusai Meijin. Black won by 2 pts.

Click Here To Show Diagram Code
[go]$$Bc Protective plays
$$ ---------------------------------------
$$ | . . . . . O X . . . X X O . . W O O . |
$$ | . . . O O O X X X B X O . . O O X O X |
$$ | . . O . . W O O O X @ O O O O X X X B |
$$ | . W O O O O X . O X . O X X X X . X . |
$$ | O O X O O X X X X X . O O X . X X O W |
$$ | . . X X O O . . O . . O X X O X O . O |
$$ | X X X X X X X X O . O O X X X O O O . |
$$ | O O O X O . X O X X X O O O X X O O . |
$$ | . O . O O . X O . . X O . O X X X O . |
$$ | O X O , O X X O . X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X . |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X , X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O . |
$$ ---------------------------------------[/go]


I added the :ws: stone on a dame after the end of play. The protective plays are indicated by :wc: and :bc: . The Black protective play at K-18 is urgent. Black does not need to protect in the bottom right corner.

Click Here To Show Diagram Code
[go]$$Wc Double ko life
$$ ---------------------------------------
$$ | . . . . . O X . . . X X O . . . O O . |
$$ | . . . O O O X X X . X O . . O O X O X |
$$ | . . O . . . O O O X O O O O O X X X . |
$$ | . . O O O O X . O X . O X X X X . X . |
$$ | O O X O O X X X X X . O O X . X X O . |
$$ | . . X X O O . . O . . O X X O X O . O |
$$ | X X X X X X X X O . O O X X X O O O . |
$$ | O O O X O . X O X X X O O O X X O O . |
$$ | . O . O O . X O . . X O . O X X X O . |
$$ | O X O , O X X O . X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X 2 X |
$$ | O O X O O X X O X X O O O O X . . X 1 |
$$ | O X X X O O O O O X X X O X 4 3 O O X |
$$ | X . X X X O . O X X X X X X X 5 X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O 6 |
$$ ---------------------------------------[/go]


If White tries anything there, Black replies simply, and the result is a double ko life for Black. Note that Black should not try to win a regular ko, since to do so would cost one move and, hence, one point. :)

Click Here To Show Diagram Code
[go]$$Bc Urgent
$$ ---------------------------------------
$$ | . . . . . O X . . . X X O . . . O O . |
$$ | . . . O O O X X X 1 X O . . O O X O X |
$$ | . . O . . . O O O X O O O O O X X X . |
$$ | . . O O O O X . O X . O X X X X . X . |
$$ | O O X O O X X X X X . O O X . X X O . |
$$ | . . X X O O . . O . . O X X O X O . O |
$$ | X X X X X X X X O . O O X X X O O O . |
$$ | O O O X O . X O X X X O O O X X O O . |
$$ | . O . O O . X O . . X O . O X X X O . |
$$ | O X O , O X X O . X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X . |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X , X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O . |
$$ ---------------------------------------[/go]


:b1: is urgent.

Click Here To Show Diagram Code
[go]$$Wc Throw-in
$$ ---------------------------------------
$$ | . . . . . O X . . 2 X X O . . . O O . |
$$ | . . . O O O X X X 1 X O . . O O X O X |
$$ | . . O . . . O O O X O O O O O X X X . |
$$ | . . O O O O X . O X . O X X X X . X . |
$$ | O O X O O X X X X X . O O X . X X O . |
$$ | . . X X O O . . O . . O X X O X O . O |
$$ | X X X X X X X X O . O O X X X O O O . |
$$ | O O O X O . X O X X X O O O X X O O . |
$$ | . O . O O . X O . . X O . O X X X O . |
$$ | O X O , O X X O . X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X . |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X , X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O . |
$$ ---------------------------------------[/go]


If Black fails to protect now, White can throw-in, taking away a liberty with sente. This is a common tesuji with semeai, but, because the danger is remote, Black may fail to notice it.

Click Here To Show Diagram Code
[go]$$Wc Another protective play is necessary
$$ ---------------------------------------
$$ | . . . . . O X . . B X X O . . . O O . |
$$ | . . . O O O X X X . X O . . O O X O X |
$$ | . . O . . W O O O X O O O O O X X X . |
$$ | . W O O O O X B O X B O X X X X . X . |
$$ | O O X O O X X X X X W O O X . X X O . |
$$ | B B X X O O W B O W W O X X O X O . O |
$$ | X X X X X X X X O B O O X X X O O O . |
$$ | O O O X O 1 X O X X X O O O X X O O . |
$$ | . O . O O 3 X O 2 . X O . O X X X O . |
$$ | O X O , O X X O 4 X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X . |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X , X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O . |
$$ ---------------------------------------[/go]


If White gets the throw-in, then after all but two of the dame are filled, :w1: and :w3: are sente.

Click Here To Show Diagram Code
[go]$$Wc Black has 3 liberties to 2
$$ ---------------------------------------
$$ | . . . . . O X . . . X X O . . . O O . |
$$ | . . . O O O X X X B X O . . O O X O X |
$$ | . . O . . W O O O X O O O O O X X X . |
$$ | . W O O O O X B O X B O X X X X . X . |
$$ | O O X O O X X X X X W O O X . X X O . |
$$ | B B X X O O W B O W W O X X O X O . O |
$$ | X X X X X X X X O B O O X X X O O O . |
$$ | O O O X O 1 X O X X X O O O X X O O . |
$$ | . O . O O 2 X O . . X O . O X X X O . |
$$ | O X O , O X X O . X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X . |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X , X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O . |
$$ ---------------------------------------[/go]


If Black connects immediately, then he does not have to make another play to win the semeai, and :w1: is gote. This result is 1 pt. better for Black than allowing the throw-in. :)


Extra credit:

Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . O X . . . X X O . . . O O . |
$$ | . . . O O O X X X . X O . . O O X O X |
$$ | . . O . . . O O O X B O O O O X X X . |
$$ | . . O O O O X . O X . O X X X X . X . |
$$ | O O X O O X X X X X . O O X . X X O . |
$$ | . . X X O O . . O . . O X X O X O . O |
$$ | X X X X X X X X O . O O X X X O O O . |
$$ | O O O X O . X O X X X O O O X X O O . |
$$ | . O . O O . X O . . X O . O X X X O . |
$$ | O X O , O X X O . X X X O . O X O . O |
$$ | . . O O O O X O O X X O O . O O O O O |
$$ | O O O X X O O X X X . X O X O . X X O |
$$ | O X X O X X X X . X X X O O X X X . X |
$$ | O O X O O X X O X X O O O O X . . X . |
$$ | O X X X O O O O O X X X O X . . O O X |
$$ | X . X X X O . O X X X X X X X , X X O |
$$ | . . X X O O . O O X X O O X O X X O . |
$$ | . X . X O . . O X O O O O O O X . X O |
$$ | X . X O O . . . . . . O X X X X X O . |
$$ ---------------------------------------[/go]


If Black has the :bc: stone, does he still have to make a protective play?

Re: Dame filling for dummies #1

Posted: Mon Sep 23, 2013 12:43 am
by Cassandra
Bill Spight wrote:If Black has the :bc: stone, does he still have to make a protective play?

Yes, and it is urgent as well.
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