Life In 19x19

Life in 19x19. Go, Weiqi, Baduk... Thats the life.
https://lifein19x19.com/

Some situations from recent games

https://lifein19x19.com/viewtopic.php?t=4736

Page 1 of 1

Some situations from recent games

Posted: Tue Sep 27, 2011 6:44 am
by HermanHiddema
Here's some situations from recent games of mine. In each, the purposes is to get the best result, which may mean you kill, you live, make seki or ko, or maybe you just gain a few points.

(edited to add solutions)
Click Here To Show Diagram Code
[go]$$W White to play
$$ ------------------+
$$ . . . O . . . . . |
$$ X . O . O X X X . |
$$ . . . O X O O O . |
$$ X . . O X X X . . |
$$ . . . O X . . . . |
$$ X . . O X O X X . |
$$ . . . X O . O O . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |[/go]
Solution:
Click Here To Show Diagram Code
[go]$$W White kills
$$ ------------------+
$$ . . . O . . . . . |
$$ X . O . O X X X . |
$$ . . . O X O O O 6 |
$$ X . . O X X X 1 . |
$$ . . . O X . 2 . 3 |
$$ X . . O X O X X 4 |
$$ . . . X O 7 O O 5 |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$W White to play
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . O O O . O . . . . . . |
$$ . . . O X X O . . . . . . . |
$$ . O O X . . X O O O O . . . |
$$ . O X . X . X O X . . O O . |
$$ . O X . . . . X . X X X O . |
$$ ----------------------------+[/go]
Solution:
Click Here To Show Diagram Code
[go]$$W White captures four stones ( :b8: @ :w5:)
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . O O O . O . . . . . . |
$$ . . . O X X O . . . . . . . |
$$ . O O X 4 3 X O O O O . . . |
$$ . O X 2 X . X O X 7 9 O O . |
$$ . O X . 1 6 5 X . X X X O . |
$$ ----------------------------+[/go]
Click Here To Show Diagram Code
[go]$$W White to play
$$ +---------------------------------------+
$$ | . . . X . . . . X . . . . . . . . . . |
$$ | . . X O O O . X O X . X O X X O . . . |
$$ | . X . X O . O O O X . X X O O O . . . |
$$ | . . . X O . O X O O . X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]
Solution:
Click Here To Show Diagram Code
[go]$$W :b6: @ :w1: White kills if black persists ('a' is auto-atari)
$$ +---------------------------------------+
$$ | . . . X . . 3 4 X 1 2 8 7 . . . . . . |
$$ | . . X O O O 5 X O X . X O X X O . . . |
$$ | . X . X O . O O O X a X X O O O . . . |
$$ | . . . X O . O X O O 9 X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]
Black cannot play like the above, so:
Click Here To Show Diagram Code
[go]$$W :b4: elsewhere. White lives, and gets to play 'a' later
$$ +---------------------------------------+
$$ | . . . X . . 3 a X 1 2 . . . . . . . . |
$$ | . . X O O O . X O X . X O X X O . . . |
$$ | . X . X O . O O O X . X X O O O . . . |
$$ | . . . X O . O X O O . X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$W Reference diagram
$$ +---------------------------------------+
$$ | . . . X 5 . 1 2 X 4 . . . . . . . . . |
$$ | . . X O O O 3 X O X . X O X X O . . . |
$$ | . X . X O . O O O X . X X O O O . . . |
$$ | . . . X O . O X O O . X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]
This way to live is simple but uninspired. The main line above gains several points compared to this.
Click Here To Show Diagram Code
[go]$$W White to play
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . O . . . . . .
$$ | . X O X . . . . .
$$ | . . X O O . . . .
$$ | . X X X O . . . .
$$ | X O X X O . . . .
$$ | . O X O O . . . .
$$ | O . O X . O . . .
$$ | . O O X X X . . .
$$ | . X X O X O . X .
$$ | . . . O X . . . .
$$ | . . . . . . . . .
$$ +------------------[/go]
Solution:
Click Here To Show Diagram Code
[go]$$W White to play
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | 7 3 O . . . . . .
$$ | 2 X O X . . . . .
$$ | 1 . X O O . . . .
$$ | . X X X O . . . .
$$ | X O X X O . . . .
$$ | . O X O O . . . .
$$ | O . O X . O . . .
$$ | 5 O O X X X . . .
$$ | 4 X X O X O . X .
$$ | . . 6 O X . . . .
$$ | . . . . . . . . .
$$ +------------------[/go]

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 7:09 am
by daniel_the_smith
#1:
Click Here To Show Diagram Code
[go]$$W White to play
$$ ------------------+
$$ . . . O . . . . . |
$$ X . O . O X X X . |
$$ . . . O X O O O 6 |
$$ X . . O X X X 1 . |
$$ . . . O X . 2 . 3 |
$$ X . . O X O X X 4 |
$$ . . . X O 7 O O 5 |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |[/go]

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 8:20 am
by entropi
Click Here To Show Diagram Code
[go]$$W White to play
$$ ------------------+
$$ . . . O . . . . . |
$$ X . O . O X X X . |
$$ . . . O X O O O . |
$$ X . . O X X X 1 . |
$$ . . . O X . 2 . 3 |
$$ X . . O X O X X 4 |
$$ . . . X O . O O 5 |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$W White to play
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . O O O . O . . . . . . |
$$ . . . O X X O . . . . . . . |
$$ . O O X . . X O O O O . . . |
$$ . O X . X . X O X . . O O . |
$$ . O X . . . . X . X X X O . |
$$ ----------------------------+[/go]
Tenuki because I cannot find anything :)


Click Here To Show Diagram Code
[go]$$W White to play
$$ +---------------------------------------+
$$ | . . . X 5 . 1 2 X 4 . . . . . . . . . |
$$ | . . X O O O 3 X O X . X O X X O . . . |
$$ | . X . X O . O O O X . X X O O O . . . |
$$ | . . . X O . O X O O . X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$W White to play
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . 7 O . . . . . .
$$ | . X O X . . . . .
$$ | . 4 X O O . . . .
$$ | 3 X X X O . . . .
$$ | X O X X O . . . .
$$ | 1 O X O O . . . .
$$ | O . O X . O . . .
$$ | 5 O O X X X . . .
$$ | 2 X X O X O . X .
$$ | . . 6 O X . . . .
$$ | . . . . . . . . .
$$ +------------------[/go]
Click Here To Show Diagram Code
[go]$$W White to play
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | 7 5 O . . . . . .
$$ | 6 X O X . . . . .
$$ | 3 4 X O O . . . .
$$ | 2 X X X O . . . .
$$ | X O X X O . . . .
$$ | 1 O X O O . . . .
$$ | O . O X . O . . .
$$ | . O O X X X . . .
$$ | . X X O X O . X .
$$ | . . . O X . . . .
$$ | . . . . . . . . .
$$ +------------------[/go]

EDIT: Hmm there may be another variation for black creating ko (unless I am totally out of tune :))
Click Here To Show Diagram Code
[go]$$W White to play
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . O . . . . . .
$$ | . X O X . . . . .
$$ | 6 4 X O O . . . .
$$ | 3 X X X O . . . .
$$ | X O X X O . . . .
$$ | 1 O X O O . . . .
$$ | O . O X . O . . .
$$ | 5 O O X X X . . .
$$ | 2 X X O X O . X .
$$ | . . 7 O X . . . .
$$ | . . . . . . . . .
$$ +------------------[/go]

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 8:33 am
by HermanHiddema
@daniel_the_smith:
Correct.
@entropi:
#1 Correct.
#3 White can do better.
#4 In response to :w1:, black will push out along the second line to escape (at :w7: in your first solution diagram), as the white group still has only one eye...

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 8:43 am
by entropi
HermanHiddema wrote: @entropi:
#4 In response to :w1:, black will push out along the second line to escape (at :w7: in your first solution diagram), as the white group still has only one eye...
:oops:

Another try:
Click Here To Show Diagram Code
[go]$$W White to play
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . 3 O . . . . . .
$$ | . X O X . . . . .
$$ | 1 2 X O O . . . .
$$ | . X X X O . . . .
$$ | X O X X O . . . .
$$ | . O X O O . . . .
$$ | O . O X . O . . .
$$ | . O O X X X . . .
$$ | . X X O X O . X .
$$ | . . . O X . . . .
$$ | . . . . . . . . .
$$ +------------------[/go]
Click Here To Show Diagram Code
[go]$$W White to play
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | 7 3 O . . . . . .
$$ | 2 X O X . . . . .
$$ | 1 . X O O . . . .
$$ | . X X X O . . . .
$$ | X O X X O . . . .
$$ | . O X O O . . . .
$$ | O . O X . O . . .
$$ | 5 O O X X X . . .
$$ | 4 X X O X O . X .
$$ | . . 6 O X . . . .
$$ | . . . . . . . . .
$$ +------------------[/go]

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 8:51 am
by jts
Click Here To Show Diagram Code
[go]$$W White to play
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . O O O . O . . . . . . |
$$ . . . O X X O . . . . . . . |
$$ . O O X 4 3 X O O O O . . . |
$$ . O X 2 X . X O X 7 9 O O . |
$$ . O X . 1 6 5 X 8 X X X O . |
$$ ----------------------------+[/go]
Click Here To Show Diagram Code
[go]$$W White to play
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . . |
$$ . . . O O O . O . . . . . . |
$$ . . . O X X O . . . . . . . |
$$ . O O X 4 3 X O O O O . . . |
$$ . O X . X . X O X 5 7 O O . |
$$ . O X . 1 2 . X 6 X X X O . |
$$ ----------------------------+[/go]
White captures 4 stones.

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 9:10 am
by HermanHiddema
@entropi:
Yes, now it is correct :)
@jts:
Correct.

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 10:23 am
by Magicwand
Click Here To Show Diagram Code
[go]$$W White to play :b6: = :w3:
$$ +---------------------------------------+
$$ | . . . X . . 1 2 X 3 4 8 7 . . . . . . |
$$ | . . X O O O 5 X O X . X O X X O . . . |
$$ | . X . X O . O O O X a X X O O O . . . |
$$ | . . . X O . O X O O 9 X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]
above will not happen...
so black will let white live by giving up three stone.
edit:
Click Here To Show Diagram Code
[go]$$W White to play =
$$ +---------------------------------------+
$$ | . . . X . . 1 2 X 3 4 . . . . . . . . |
$$ | . . X O O O . X O X . X O X X O . . . |
$$ | . X . X O . O O O X . X X O O O . . . |
$$ | . . . X O . O X O O . X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]
infact white should tenuki and take sente because it is alive.. ??

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 10:52 am
by HermanHiddema
@Magicwand:
Yes, basically correct, but black should only give one stone, of course, and take sente:
Click Here To Show Diagram Code
[go]$$W :b2: is sente
$$ +---------------------------------------+
$$ | . . . X . . 1 3 X 2 . . . . . . . . . |
$$ | . . X O O O . X O X . X O X X O . . . |
$$ | . X . X O . O O O X . X X O O O . . . |
$$ | . . . X O . O X O O . X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]
So white should throw in first, as it is free and may give better endgame later:
Click Here To Show Diagram Code
[go]$$W White can play a at any time to create aji.
$$ +---------------------------------------+
$$ | . . . X . . 3 . X 1 2 . a . . . . . . |
$$ | . . X O O O . X O X . X O X X O . . . |
$$ | . X . X O . O O O X . X X O O O . . . |
$$ | . . . X O . O X O O . X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]

The following resistance is pointless and loses sente:
Click Here To Show Diagram Code
[go]$$W :w7: at :w1:, :b8: at :w3:
$$ +---------------------------------------+
$$ | . . . X . 9 2 . X 1 3 6 . . . . . . . |
$$ | . . X O O O 5 X O X 4 X O X X O . . . |
$$ | . X . X O . O O O X . X X O O O . . . |
$$ | . . . X O . O X O O 0 X O . . , . . . |
$$ | . . . X O O X X X O O X O . . . . . . |
$$ | . . . X . X . . . X X O O . . . . . . |
$$ | . . . . . . X . . . . . . . . . . . . |[/go]

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 11:12 am
by jts
As I've mentioned before I tend to fixate on insignificant details. A question for Herman (or anyone else, really) on question 2: I'm wondering whether one should use the first moves in that sequence as ko threats. Would you ignore the situation for as long as possible in the hope that your opponent has missed the sequence and might miss the opportunity to defend, or would you use the beginning of that sequence as medium-sized ko threats long before finishing the sequence became profitable?

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 11:22 am
by Magicwand
jts wrote:
As I've mentioned before I tend to fixate on insignificant details. A question for Herman (or anyone else, really) on question 2: I'm wondering whether one should use the first moves in that sequence as ko threats. Would you ignore the situation for as long as possible in the hope that your opponent has missed the sequence and might miss the opportunity to defend, or would you use the beginning of that sequence as medium-sized ko threats long before finishing the sequence became profitable?
if i can sense that my opponent misread then i usually (all depends on the situation) wait till the end to trigger the unexpected bomb :)

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 11:23 am
by HermanHiddema
jts wrote:
As I've mentioned before I tend to fixate on insignificant details. A question for Herman (or anyone else, really) on question 2: I'm wondering whether one should use the first moves in that sequence as ko threats. Would you ignore the situation for as long as possible in the hope that your opponent has missed the sequence and might miss the opportunity to defend, or would you use the beginning of that sequence as medium-sized ko threats long before finishing the sequence became profitable?
Since the profit is rather small, 8 points gote, #2 is very much an endgame sequence. Using the first three moves as ko threats in the middle game is therefore entirely feasible, as each of these move threatens to kill the entire group.

In the endgame, I would usually just play it when it gets big enough. Perhaps, if I were slightly behind, I might leave it and hope my opponent missed it :)

Re: Some situations from recent games

Posted: Tue Sep 27, 2011 11:43 am
by jts
HermanHiddema wrote:Perhaps, if I were slightly behind, I might leave it and hope my opponent missed it
Thanks! I always forget about the whole "knowing who's ahead" thing! :roll:
All times are UTC-07:00
Page 1 of 1

Powered by phpBB® Forum Software © phpBB Limited