It is currently Thu Oct 31, 2024 4:46 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 7 posts ] 
Author Message
Offline
 Post subject: 1000 year ko
Post #1 Posted: Sun Apr 09, 2017 7:10 am 
Beginner

Posts: 1
Liked others: 0
Was liked: 0
Rank: IGS 1 dan
IGS: deanr
Hi. I recently found myself in a 1000-year ko on IGS. I could not figure out how to conclude the game and eventually suggested that one of us resign, followed by an accepted new game challenge, followed by 4 moves, followed by the other person resigning. Is there a proper way to recognize a gigo?

Top
 Profile  
 
Offline
 Post subject: Re: 1000 year ko
Post #2 Posted: Sun Apr 09, 2017 7:17 am 
Lives with ko

Posts: 211
Liked others: 16
Was liked: 62
Rank: KGS 1k EGF 2k
KGS: Schachus12
What? no...
In a 10000-year ko, if neither player wants to play a ko then usually either one can make seki. At least when there is nothing else on the board, there is one one player who will hapily make seki, because it wins the game for him(so if there is really nothing else left, maybe the other one should have made a disadvantegous ko.., better then just losing, usually it would be resolved a little(but not much) earlier). This is not like triple ko..

Top
 Profile  
 
Offline
 Post subject: Re: 1000 year ko
Post #3 Posted: Sun Apr 09, 2017 9:10 am 
Lives in gote

Posts: 388
Liked others: 295
Was liked: 64
IGS: 4k
Universal go server handle: BlindGroup
I played a game last night with a 1000 year ko. I think my opponent played it properly. So, maybe this might be a useful example. The game was on KGS and my opponent was ranked as 7k. However, the rank was brand new, and he was just getting back into go after a long hiatus. So, I suspect he's probably a bit stronger than 7k. He seemed to make two big mistakes (got away with one...) in the fuseki, but otherwise, he dominated me.

Here are the key moves:
Move 127: He starts harassing my L+2 group, and as I often do, I misplay a position that I know well.
Move 135: He establishes a 1000 year ko. As Schachus notes, opponent can create the ko by playing at S19 or convert to seki by playing T19. I can also start the ko by playing T19, but I can't force seki.
Move 265: Opponents initiates ko fight since I'm not short on ko threats.
Move 288: I run out of ko threats and lose the group after the next move.



Attachments:
2017-04-09 1000 year ko.sgf [4.88 KiB]
Downloaded 695 times
Top
 Profile  
 
Offline
 Post subject: Re: 1000 year ko
Post #4 Posted: Sun Apr 09, 2017 10:03 am 
Lives with ko

Posts: 211
Liked others: 16
Was liked: 62
Rank: KGS 1k EGF 2k
KGS: Schachus12
I'm sorry to say that, but I think you(and your opponent) misread the L+D there. THis is not in fact a 10000-year ko, because your opponents play at t19 does not make seki, but it kills your corner in a bent four in the corner shape. So this is what he should have done instead of starting the ko(at least under japanese rules, under chinese he will have play a ko in the end to prove that bent 4 in the corner is dead).

Top
 Profile  
 
Offline
 Post subject: Re: 1000 year ko
Post #5 Posted: Sun Apr 09, 2017 10:09 am 
Lives in gote

Posts: 388
Liked others: 295
Was liked: 64
IGS: 4k
Universal go server handle: BlindGroup
Schachus wrote:
I'm sorry to say that, but I think you(and your opponent) misread the L+D there. THis is not in fact a 10000-year ko, because your opponents play at t19 does not make seki, but it kills your corner in a bent four in the corner shape. So this is what he should have done instead of starting the ko(at least under japanese rules, under chinese he will have play a ko in the end to prove that bent 4 in the corner is dead).


Good to know. Thanks for correcting me. Not familiar with this, but will take a look. That said, I guess I was dead either way...

Top
 Profile  
 
Offline
 Post subject: Re: 1000 year ko
Post #6 Posted: Sun Apr 09, 2017 10:29 am 
Honinbo

Posts: 10905
Liked others: 3651
Was liked: 3374
Before we get to the position in question:

Click Here To Show Diagram Code
[go]$$Bc Move 127 Variation
$$ ---------------------------------------
$$ | . . . . . . . X 1 . . . . . . . . . . |
$$ | . . O O . O O X O . . . O . X O O . . |
$$ | . . X . . O X X O O O O O X . X O . . |
$$ | . . . X . O X O . O X X O X . X O O . |
$$ | . . . . . O X X O X X O X X . O X O . |
$$ | . . X . . . . . X . . . . . . . X X . |
$$ | . . . . . . . . . . . . . . X . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . O . O . . |
$$ | . . . , . . X . . , . . . . . , . . . |
$$ | . . . . . X O O O . O . . . . . . . . |
$$ | . . . . . X O . O X . . . . . . . . . |
$$ | . . . X . X O O X O O . . X O O O O . |
$$ | . . X O O X X X X X O . . X X X X X . |
$$ | . . X . . . . X O O X X . . . . X O . |
$$ | . . O O . . X O . O O O . . . O O X . |
$$ | . . . . O . X O O . . . . O O . O X . |
$$ | . . . . . X . X O . . . . . . X X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Black might have done well to play B 127 here. :)

Click Here To Show Diagram Code
[go]$$Bc Move 135: Not 10,000 year ko
$$ ---------------------------------------
$$ | . . . . . . . X . . . . . . X X O . . |
$$ | . . O O . O O X O . O . O . X O O O 1 |
$$ | . . X . . O X X O O O O O X . X O . X |
$$ | . . . X . O X O . O X X O X . X O O O |
$$ | . . . . . O X X O X X O X X . O X O X |
$$ | . . X . . . . . X . . . . . . . X X . |
$$ | . . . . . . . . . . . . . . X . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . O . O . . |
$$ | . . . , . . X . . , . . . . . , . . . |
$$ | . . . . . X O O O . O . . . . . . . . |
$$ | . . . . . X O . O X . . . . . . . . . |
$$ | . . . X . X O O X O O . . X O O O O . |
$$ | . . X O O X X X X X O . . X X X X X . |
$$ | . . X . . . . X O O X X . . . . X O . |
$$ | . . O O . . X O . O O O . . . O O X . |
$$ | . . . . O . X O O . . . . O O . O X . |
$$ | . . . . . X . X O . . . . . . X X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


This is not a 10,000 year ko.

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


White can play a throw-in to make a ko.

Click Here To Show Diagram Code
[go]$$Bc Bent four in the corner
$$ ---------------------------------------
$$ | . . . . . . . X . . . . . . X X O . 1 |
$$ | . . O O . O O X O . O . O . X O O O X |
$$ | . . X . . O X X O O O O O X . X O . X |
$$ | . . . X . O X O . O X X O X . X O O O |
$$ | . . . . . O X X O X X O X X . O X O X |
$$ | . . X . . . . . X . . . . . . . X X . |
$$ | . . . . . . . . . . . . . . X . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . O . O . . |
$$ | . . . , . . X . . , . . . . . , . . . |
$$ | . . . . . X O O O . O . . . . . . . . |
$$ | . . . . . X O . O X . . . . . . . . . |
$$ | . . . X . X O O X O O . . X O O O O . |
$$ | . . X O O X X X X X O . . X X X X X . |
$$ | . . X . . . . X O O X X . . . . X O . |
$$ | . . O O . . X O . O O O . . . O O X . |
$$ | . . . . O . X O O . . . . O O . O X . |
$$ | . . . . . X . X O . . . . . . X X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Or Black can kill with Bent Four in the Corner. :)

As Schachus pointed out.

Edit: BTW, Black 135 is a middling endgame play. It can wait.

Also:

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


:b1:, to make ko in the corner, is a large endgame play. It is better than Black 131 in the game, but it would still have been premature.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.


Last edited by Bill Spight on Sun Apr 09, 2017 11:15 am, edited 1 time in total.

This post by Bill Spight was liked by: BlindGroup
Top
 Profile  
 
Offline
 Post subject: Re: 1000 year ko
Post #7 Posted: Sun Apr 09, 2017 10:32 am 
Honinbo

Posts: 10905
Liked others: 3651
Was liked: 3374
Schachus wrote:
I'm sorry to say that, but I think you(and your opponent) misread the L+D there. THis is not in fact a 10000-year ko, because your opponents play at t19 does not make seki, but it kills your corner in a bent four in the corner shape. So this is what he should have done instead of starting the ko(at least under japanese rules, under chinese he will have play a ko in the end to prove that bent 4 in the corner is dead).


Under Chinese rules he can remove ko threats before playing either of the two kos involved. :)

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 7 posts ] 

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