It is currently Sun May 04, 2025 6:36 am

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


Board index » Improve Your Game » Study Group

All times are UTC - 8 hours [ DST ]



Post new topic Reply to topic  Page 1 of 1
  [ 7 posts ] 
  Print view Previous topic | Next topic 
Author Message
Offline Hushfield
 Post subject: 4 life and death problems.
Post #1 Posted: Thu Aug 14, 2014 1:44 am 
Lives in gote
User avatar

Posts: 359
Location: Ghent, Belgium
Liked others: 72
Was liked: 199
GD Posts: 11
KGS: Hushfield
For anyone that's interested: below you can find 4 problems from a lecture on life and death I recently attended at School Pink Stones.

Click Here To Show Diagram Code
[go]$$c Black to play
$$ ----------------
$$ | . . . . . . . .
$$ | . . X . . . . .
$$ | . X . . . . . .
$$ | . . X X X . . .
$$ | . . O O . X . .
$$ | . . X O . . . .
$$ | . . . O X . . .
$$ | . . O X . X . .
$$ | O O O X . . . .
$$ | X X X X . . . .
$$ | . . . . . . . .[/go]


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


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


Click Here To Show Diagram Code
[go]$$c Black to play
$$ . . . . . . . . |
$$ . . . . . X . . |
$$ . . . . . . . . |
$$ . . . . . . . . |
$$ . . . O X X X . |
$$ . . X . . O X . |
$$ . . X . X O . . |
$$ . . . . O . O . |
$$ . . . . . . . . |
$$ ---------------[/go]


I'll post the answers after a few people have had a go at these problems.

If you're stuck and need a hint:
If there really is no better solution, ko might be a valid answer. But if there is a way to kill unconditionally, getting a ko represents failure. I always feel cheated when the answer to a life and death problem turns out to be ko, but it makes sense: in real games, there's no one standing next to you saying which groups can be killed unconditionally, and which ones turn into ko. Even if you get the first (few) move(s) correct, if a solution is ko and you thought it was a clean kill, you got the problem wrong. The difference between killing and starting a ko can be a big difference in a real game, after all.

This post by Hushfield was liked by: drmwc
Top
 Profile  
 
Offline Marcus
 Post subject: Re: 4 life and death problems.
Post #2 Posted: Thu Aug 14, 2014 8:00 am 
Gosei

Posts: 1387
Liked others: 139
Was liked: 111
GD Posts: 209
KGS: Marcus316
I think I've got the first one. I keep refuting my solutions to the 2nd one. Will continue later. If anyone has a refutation of the below candidate solution, let me know. :D

Problem 1:
Click Here To Show Diagram Code
[go]$$c First Move
$$ ----------------
$$ | . . . . . . . .
$$ | . . X . . . . .
$$ | . X . . . . . .
$$ | . . X X X . . .
$$ | . . O O . X . .
$$ | . . X O . . . .
$$ | . 1 . O X . . .
$$ | . . O X . X . .
$$ | O O O X . . . .
$$ | X X X X . . . .
$$ | . . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$c Var 1
$$ ----------------
$$ | . . . . . . . .
$$ | . . X . . . . .
$$ | . X . . . . . .
$$ | . . X X X . . .
$$ | 5 6 O O . X . .
$$ | 7 2 C O . . . .
$$ | 3 1 4 O X . . .
$$ | . . O X . X . .
$$ | O O O X . . . .
$$ | X X X X . . . .
$$ | . . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$c Var 2
$$ ----------------
$$ | . . . . . . . .
$$ | . . X . . . . .
$$ | . X . . . . . .
$$ | . . X X X . . .
$$ | 3 7 O O . X . .
$$ | 6 4 C O . . . .
$$ | 5 1 2 O X . . .
$$ | . . O X . X . .
$$ | O O O X . . . .
$$ | X X X X . . . .
$$ | . . . . . . . .[/go]
Top
 Profile  
 
Offline Marcus
 Post subject: Re: 4 life and death problems.
Post #3 Posted: Thu Aug 14, 2014 8:27 am 
Gosei

Posts: 1387
Liked others: 139
Was liked: 111
GD Posts: 209
KGS: Marcus316
Here's the best I can do for Problem 2:

All I could force was ko. First variation was what I thought would work, second is the better W defense:

Click Here To Show Diagram Code
[go]$$c W dies here, so see next variation ...
$$ --------------------
$$ . . X X 6 2 4 8 7 . |
$$ . . X O O 5 1 O O 9 |
$$ . . X O . O 3 X O . |
$$ , . X O O O X X X X |
$$ . . . X X X . . . . |
$$ . . . . . . X . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |[/go]


Click Here To Show Diagram Code
[go]$$c Ko?
$$ --------------------
$$ . . X X 6 2 4 . 7 . |
$$ . . X O O 5 1 O O 9 |
$$ . . X O . O 3 X O 8 |
$$ , . X O O O X X X X |
$$ . . . X X X . . . . |
$$ . . . . . . X . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |[/go]
Top
 Profile  
 
Offline Marcus
 Post subject: Re: 4 life and death problems.
Post #4 Posted: Thu Aug 14, 2014 8:47 am 
Gosei

Posts: 1387
Liked others: 139
Was liked: 111
GD Posts: 209
KGS: Marcus316
Problem 3:

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


Click Here To Show Diagram Code
[go]$$c Var 1
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . X . . . . . . .
$$ | . . . X X X X . . .
$$ | . X X O 2 O X . . .
$$ | X O X O . O X . . ,
$$ | . O O 3 . O O X . .
$$ | . O 4 1 . O X X . .
$$ | . . . 5 O X X . . .
$$ ---------------------[/go]


Click Here To Show Diagram Code
[go]$$c Var 2 - :b11: at :bc:
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . X . . . . . . .
$$ | . . . X X X X . . .
$$ | 0 X X O 9 O X . . .
$$ | B O X O . O X . . ,
$$ | 7 O O 2 6 O O X . .
$$ | 8 O . 1 3 O X X . .
$$ | . . 4 5 C X X . . .
$$ ---------------------[/go]


Click Here To Show Diagram Code
[go]$$c Var 3
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . X . . . . . . .
$$ | . . . X X X X . . .
$$ | . X X O 2 O X . . .
$$ | X O X O 7 O X . . ,
$$ | . O O 5 . O O X . .
$$ | . O . 1 4 O X X . .
$$ | . . 6 3 O X X . . .
$$ ---------------------[/go]


Click Here To Show Diagram Code
[go]$$c Var 4
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . X . . . . . . .
$$ | . . . X X X X . . .
$$ | . X X O 2 O X . . .
$$ | X O X O . O X . . ,
$$ | . O O 4 6 O O X . .
$$ | . O . 1 5 O X X . .
$$ | . 7 . 3 C X X . . .
$$ ---------------------[/go]
Top
 Profile  
 
Offline drmwc
 Post subject: Re: 4 life and death problems.
Post #5 Posted: Sat Aug 16, 2014 3:33 am 
Lives in gote
User avatar

Posts: 452
Liked others: 74
Was liked: 100
Rank: 4 Dan European
Number 4:

Click Here To Show Diagram Code
[go]$$c Black to play
$$ . . . . . . . . |
$$ . . . . . X . . |
$$ . . . . . . . . |
$$ . . . . . . . . |
$$ . . . O X X X . |
$$ . . X 3 2 O X . |
$$ . . X 4 X O 7 . |
$$ . . . 1 O . O 8 |
$$ . . 5 . 9 6 . . |
$$ ---------------[/go]


Black kills through a double ko.

This post by drmwc was liked by: ez4u
Top
 Profile  
 
Offline cornucopia
 Post subject: Re: 4 life and death problems.
Post #6 Posted: Sat Aug 16, 2014 8:00 pm 
Dies in gote
User avatar

Posts: 67
Location: Belgium
Liked others: 19
Was liked: 16
Rank: EGF 9 kyu
KGS: lowlykyu
DGS: cornucopia
OGS: cornucopia
Thanks Hushfield, they look really interesting! I'm going to take them to the GGG studygroup tomorrow! I'll keep you posted on the achieved results :mrgreen:

_________________
Avatar photo courtesy Judith van Dam/EuroGoTV
Top
 Profile  
 
Offline Hushfield
 Post subject: Re: 4 life and death problems.
Post #7 Posted: Mon Aug 18, 2014 12:05 am 
Lives in gote
User avatar

Posts: 359
Location: Ghent, Belgium
Liked others: 72
Was liked: 199
GD Posts: 11
KGS: Hushfield
You can find the solutions below:

Problem 1:
Click Here To Show Diagram Code
[go]$$c Black kills unconditionally
$$ ----------------
$$ | . . . . . . . .
$$ | . . X . . . . .
$$ | . X . . . . . .
$$ | . . X X X . . .
$$ | 5 . O O . X . .
$$ | . 2 X O . . . .
$$ | 3 1 4 O X . . .
$$ | . . O X . X . .
$$ | O O O X . . . .
$$ | X X X X . . . .
$$ | . . . . . . . .[/go]
Problem 2:
Click Here To Show Diagram Code
[go]$$c Black can get a ko
$$ --------------------
$$ . . X X 4 3 6 7 8 . |
$$ . . X O O . 1 O O . |
$$ . . X O . O 2 X O 5 |
$$ , . X O O O X X X X |
$$ . . . X X X . . . . |
$$ . . . . . . X . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |[/go]
Problem 3:
Click Here To Show Diagram Code
[go]$$c Black can get a ko
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . X . . . . . . .
$$ | . . . X X X X . . .
$$ | . X X O . O X . . .
$$ | X O X O . O X . . ,
$$ | . O O . . O O X . .
$$ | 7 O 6 1 3 O X X . .
$$ | 8 5 4 2 O X X . . .
$$ ---------------------[/go]
Problem 4:
Click Here To Show Diagram Code
[go]$$c Black kills through double ko
$$ . . . . . . . . |
$$ . . . . . X . . |
$$ . . . . . . . . |
$$ . . . . . . . . |
$$ . . . O X X X . |
$$ . . X 3 2 O X . |
$$ . . X 4 X O 7 . |
$$ . . . 1 O . O 8 |
$$ . . 5 . 9 6 . . |
$$ ---------------[/go]
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  Page 1 of 1
  [ 7 posts ] 

Board index » Improve Your Game » Study Group

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