It is currently Tue May 13, 2025 11:02 pm

View unanswered posts | View active topics View unread posts | View new posts | View your posts


Board index » Life In 19x19.com General Topics » Beginners

All times are UTC - 8 hours [ DST ]



Post new topic Reply to topic  Page 1 of 1
  [ 10 posts ] 
  Print view Previous topic | Next topic 
Author Message
Offline ikkyu
 Post subject: Quick question about a net
Post #1 Posted: Sun Jun 02, 2013 1:51 pm 
Lives with ko

Posts: 131
Liked others: 2
Was liked: 3
Rank: 17-18k
In watching IGS today, I saw this game where white had just played the marked stone. Before black made his next move, I thought that if he played on the triangle at M12, he could capture the white group in the middle.

He ended up playing H4 next, so it seems to me that I must be wrong since both players are far above my level. However, as much as I look at it, it seems that M12 works. What am I missing?

Click Here To Show Diagram Code
[go]$$c
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . X . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . X . T . . . . . . . |
$$ | . . . . . . . X X O W . . . . . . . . |
$$ | . . . , . . . X O O X X X . . , . . . |
$$ | . . . . . . X O O . O . . O . . X . . |
$$ | . . . . . . X X O . O X X O . O X . . |
$$ | . . . . . O . O X . X O O . . O X . . |
$$ | . . . . . . . O X . X . . O O X X . . |
$$ | . . . . . . . X O . . . . . O O O . . |
$$ | . . . O . . . . O , X . . O X , . . . |
$$ | . . . . . . . . . . . . . O . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Top
 Profile  
 
Offline lightvector
 Post subject: Re: Quick question about a net
Post #2 Posted: Sun Jun 02, 2013 2:02 pm 
Lives in sente

Posts: 759
Liked others: 114
Was liked: 916
Rank: maybe 2d
This sequence might not be optimal, but it shows that M12 doesn't kill white.

Click Here To Show Diagram Code
[go]$$c White pushes and cuts everywhere
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . X . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . 7 . . . . . . . . |
$$ | . . . . . . . . . 4 3 6 . . . . . . . |
$$ | . . . . . . . . 5 X 2 1 9 . . . . . . |
$$ | . . . . . . . X X O O 8 0 . . . . . . |
$$ | . . . , . . . X O O X X X . . , . . . |
$$ | . . . . . . X O O . O . . O . . X . . |
$$ | . . . . . . X X O . O X X O . O X . . |
$$ | . . . . . O . O X . X O O . . O X . . |
$$ | . . . . . . . O X . X . . O O X X . . |
$$ | . . . . . . . X O . . . . . O O O . . |
$$ | . . . O . . . . O , X . . O X , . . . |
$$ | . . . . . . . . . . . . . O . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Click Here To Show Diagram Code
[go]$$c And captures something
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . X . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . X . . . . . . . . |
$$ | . . . . . . . . . O X O 3 . . . . . . |
$$ | . . . . . . . . X X O X X 2 . . . . . |
$$ | . . . . . . . X X O O O O 1 5 . . . . |
$$ | . . . , . . . X O O B B B 4 . , . . . |
$$ | . . . . . . X O O . O . 6 O . . X . . |
$$ | . . . . . . X X O . O B B O . O X . . |
$$ | . . . . . O . O X . X O O . . O X . . |
$$ | . . . . . . . O X . X . . O O X X . . |
$$ | . . . . . . . X O . . . . . O O O . . |
$$ | . . . O . . . . O , X . . O X , . . . |
$$ | . . . . . . . . . . . . . O . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Top
 Profile  
 
Offline ikkyu
 Post subject: Re: Quick question about a net
Post #3 Posted: Sun Jun 02, 2013 2:49 pm 
Lives with ko

Posts: 131
Liked others: 2
Was liked: 3
Rank: 17-18k
Okay. Thanks.
Top
 Profile  
 
Offline Thunkd
 Post subject: Re: Quick question about a net
Post #4 Posted: Mon Jun 03, 2013 6:49 am 
Dies with sente
User avatar

Posts: 88
Liked others: 2
Was liked: 13
Rank: KGS 6K
lightvector wrote:
Click Here To Show Diagram Code
[go]$$c And captures something
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . X . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . X . . . . . . . . |
$$ | . . . . . . . . . O X O X . . . . . . |
$$ | . . . . . . . . X X O X X O . . . . . |
$$ | . . . . . . . X X O O O O X X . . . . |
$$ | . . . , . . . X O O X X X O . , . . . |
$$ | . . . . . . X O O . O . O O . . X . . |
$$ | . . . . . . X X O . O X X O . O X . . |
$$ | . . . . . O . O X . X O O . . O X . . |
$$ | . . . . . . . O X . X . . O O X X . . |
$$ | . . . . . . . X O . . . . . O O O . . |
$$ | . . . O . . . . O , X . . O X , . . . |
$$ | . . . . . . . . . . . . . O . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


But this might not be a bad result for black.
Top
 Profile  
 
Offline skydyr
 Post subject: Re: Quick question about a net
Post #5 Posted: Mon Jun 03, 2013 7:38 am 
Oza

Posts: 2495
Location: DC
Liked others: 157
Was liked: 443
Universal go server handle: skydyr
Online playing schedule: When my wife is out.
Well...

Click Here To Show Diagram Code
[go]$$c And captures something
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . X . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . X . . . . . . . . |
$$ | . . . . . . . . . O X O X . . . . . . |
$$ | . . . . . . . . X X O X X O . . . . . |
$$ | . . . . . . . X X O O O O X X . . . . |
$$ | . . . , . . . X W O X X X W . , . . . |
$$ | . . . . . . X O O . O . O O . . X . . |
$$ | . . . . . . X X O . O X X O . O X . . |
$$ | . . . . . O . O X . X O O . . O X . . |
$$ | . . . . . . . O X . X . . O O X X . . |
$$ | . . . . . . . X O . . . . . O O O . . |
$$ | . . . O . . . . O , X . . O X , . . . |
$$ | . . . . . . . . . . . . . O . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . M . . . . M . . . . . |
$$ ---------------------------------------[/go]


If we count this, white has secured an area between the 4 marked points of about 52 points. White has a moyo on the bottom left of maybe another 40 or so, plus a likely corner in the lower right of another 20ish and a top left of a few points. Black has a loose moyo of a bit over 100 points, but it's still quite easy for white to invade, and the dead white stones have some aji as well. I think the left side could end up as a wash between the two. Certainly if black pushes to get a lot there, white's moyo will solidify pretty fast.

As a result, both sides maybe have the same total of potential + cash, but white has 50 points of territory already, while black has maybe 10-20 on the right side, and I think black is easier to invade or reduce than white.

This post by skydyr was liked by: Akura
Top
 Profile  
 
Offline Thunkd
 Post subject: Re: Quick question about a net
Post #6 Posted: Tue Jun 04, 2013 6:53 am 
Dies with sente
User avatar

Posts: 88
Liked others: 2
Was liked: 13
Rank: KGS 6K
skydyr wrote:
Well...

So if you don't like this, what would you have preferred Black to do in this situation. What would your alternate plan for the game have been?
Top
 Profile  
 
Offline skydyr
 Post subject: Re: Quick question about a net
Post #7 Posted: Tue Jun 04, 2013 10:13 am 
Oza

Posts: 2495
Location: DC
Liked others: 157
Was liked: 443
Universal go server handle: skydyr
Online playing schedule: When my wife is out.
Thunkd wrote:
skydyr wrote:
Well...

So if you don't like this, what would you have preferred Black to do in this situation. What would your alternate plan for the game have been?


As black, I think the 5 cutting stones need to be kept alive to keep white from gaining a strong position and to attack the center stones to build the top and right. Black also has more aji with the bottom group as long as white's group is weak. Perhaps one move over from the proposed net (N12)? I'm not entirely sure.
Top
 Profile  
 
Offline Unusedname
 Post subject: Re: Quick question about a net
Post #8 Posted: Tue Jun 04, 2013 11:36 am 
Lives in gote
User avatar

Posts: 447
Liked others: 137
Was liked: 68
Rank: kgs 5kyu
KGS: Unusedname
Click Here To Show Diagram Code
[go]$$c And captures something
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . X . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . X . . . . . . . . |
$$ | . . . . . . . . . O X O X . . . . . . |
$$ | . . . . . . . . X X O X X O . . . . . |
$$ | . . . . . . . X X O O O O X X . . . . |
$$ | . . . , . . . X O O X X X O . , . . . |
$$ | . . . . . . X O O . O . O O . . X . . |
$$ | . . . . . . X X O . O X X O . O X . . |
$$ | . . . . . O . O X . X O O . . O X . . |
$$ | . . . . . 2 . O X . X . . O O X X . . |
$$ | . . . . . . 1 X W . . . . . O O O . . |
$$ | . . . O . . . . W , X . . O X , . . . |
$$ | . . . . . . . 3 . . . . . O . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . M . . . . M . . . . . |
$$ ---------------------------------------[/go]


White's position on the bottom doesn't look that secure.
Can't black capture these cutting stones and live on the bottom?
Top
 Profile  
 
Offline Joaz Banbeck
 Post subject: Re: Quick question about a net
Post #9 Posted: Tue Jun 04, 2013 12:30 pm 
Judan
User avatar

Posts: 5546
Location: Banbeck Vale
Liked others: 1104
Was liked: 1457
Rank: 1D AGA
GD Posts: 1512
Kaya handle: Test
He can almost certainly live on the bottom if he chases them:

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

_________________
Help make L19 more organized. Make an index: https://lifein19x19.com/viewtopic.php?f=14&t=5207
Top
 Profile  
 
Offline skydyr
 Post subject: Re: Quick question about a net
Post #10 Posted: Tue Jun 04, 2013 12:52 pm 
Oza

Posts: 2495
Location: DC
Liked others: 157
Was liked: 443
Universal go server handle: skydyr
Online playing schedule: When my wife is out.
Unusedname wrote:
[
White's position on the bottom doesn't look that secure.
Can't black capture these cutting stones and live on the bottom?


Yeah, looking over this earlier I realize I made an assumption that white could take this but didn't really look at it too closely.
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  Page 1 of 1
  [ 10 posts ] 

Board index » Life In 19x19.com General Topics » Beginners

All times are UTC - 8 hours [ DST ]

Who is online

Users browsing this forum: No registered users and 1 guest

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group