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A life and death problem from my last game

Posted: Wed Oct 03, 2012 3:50 pm
by Samura
Hi, my first post here,

In the last game I played, as white, this situation happened (it's only a fragment of the board). I had only 30 seconds (byo-yomi) to try to kill the black group. I played R1, but the black player (another 18k) got to live.

My question is: this is an easy problem? I'm am currently KGS 18k, how strong one probably must be to solve this problem in a game in 30 seconds? There is some "theory" to guide me?

I'm a newbie, if this is a too lame question, I'm sorry. It's just that it was the first life and death problem that arose in my games and I'm really curious! Thank you.

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

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 4:08 pm
by xed_over
:w1: in your diagram doesn't do anything

how about this instead?

Click Here To Show Diagram Code
[go]$$Wc what is black going to do?
$$ . . . . . . . . . . . |
$$ . . . . . . . . . . . |
$$ . . . . . . . . . O . |
$$ . , . . . . . O O . O |
$$ . . . . . . O . X O . |
$$ . . . . . O X 1 . X X |
$$ . . . . . . . . . . . |
$$ ----------------------[/go]


or even this still
Click Here To Show Diagram Code
[go]$$Wc should still kill
$$ . . . . . . . . . . . |
$$ . . . . . . . . . . . |
$$ . . . . . . . . . O . |
$$ . , . . . . . O O . O |
$$ . . . . . . O . X O . |
$$ . . . . . O X 2 . X X |
$$ . . . . 1 . 3 . . . . |
$$ ----------------------[/go]

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 4:09 pm
by sequencer
Hi Samura,

welcome to the forum! It is a simple problem, I think a 15 kyu should solve it within 30s.

There are books around, like "Life and death", "Graded go problems", or you could try http://www.goproblems.coom.

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 4:16 pm
by skydyr
It's not an absolute beginner problem, but it's on the easier side as far as these things go. I've included a solution (hidden) but do try and figure it out yourself for a bit first.
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . |
$$ . . . . . . . O . |
$$ . . . . . O O . O |
$$ . . . . O 1 X O . |
$$ . . . O X X 2 X X |
$$ . . O . 3 4 . 5 . |
$$ ------------------[/go]


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


Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . |
$$ . . . . . . . O . |
$$ . . . . . O O . O |
$$ . . . . O 1 X O . |
$$ . . . O X X . X X |
$$ . . O . 3 . 2 . . |
$$ ------------------[/go]


Click Here To Show Diagram Code
[go]$$Wc 5 at marked stone
$$ . . . . . . . . . |
$$ . . . . . . . O . |
$$ . . . . . O O . O |
$$ . . . . O 1 B O . |
$$ . . . O X X 3 X X |
$$ . . O . 2 . 4 . . |
$$ ------------------[/go]

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 4:20 pm
by Samura
Thank you all for your replies!

PS: Well, I had to play at N1 first because of this context in the game:

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

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 4:22 pm
by Samura
sequencer,

I bought both "Life and Death (Elementary Series)" and "Graded Problems Vol 1 & 2" and they are at the moment my priority in the reading list! :tmbup:

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 5:20 pm
by xed_over
Samura wrote:PS: Well, I had to play at N1 first because of this context in the game:

ah, makes more sense now :)

then I think
my w P1 and skydyr's w q3 are both good first moves to kill -- there may be others

maybe I shouldn't ask, but what was your move(s) that allowed black to live?

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 5:28 pm
by jts
xed_over wrote:
Samura wrote:PS: Well, I had to play at N1 first because of this context in the game:

ah, makes more sense now :)

then I think
my w P1 and skydyr's w q3 are both good first moves to kill -- there may be others

maybe I shouldn't ask, but what was your move(s) that allowed black to live?

Op says he played r1, I'm guessing b followed with s1.

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 5:30 pm
by jts
Samura wrote:Thank you all for your replies!

PS: Well, I had to play at N1 first because of this context in the game:

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

There may be even more context, but try to read out what happens if w says "screw it" and plays q2 anyway.

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 5:38 pm
by Samura
The game followed as this (remember that I'm a 18k playing with 30s).

I played instinctively at R1 to kill some possible bent three shape, as it's a very common solution in beginner tsumegos. So, this is an instance where memorized learning didn't worked. :mad:

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

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 5:51 pm
by Samura
jts wrote:There may be even more context, but try to read out what happens if w says "screw it" and plays q2 anyway.


I must admit that to sacrifice 3 stones is yet unthinkable to me... but I'm aware that sacrifices are very common in pro games. I'll try to think about this problem. Thank you!

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 6:44 pm
by jts
Well, which stone/s will you actually sacrifice by playing at q2?

Re: A life and death problem from my last game

Posted: Wed Oct 03, 2012 6:56 pm
by Samura
Ops, we need some context again:

I would lose the M2 group playing Q2, I think. But I still need to read all possibilities... Amazing how this turned in a great tsumego! (for me at least).

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

Re: A life and death problem from my last game

Posted: Thu Oct 04, 2012 8:36 am
by jts
The context is important, isn't it? :) In this case, this is what I was trying to get at: if you had one more liberty for your three surrounded stones...

Click Here To Show Diagram Code
[go]$$c White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . X . X . . . . . . . |
$$ | . . . . . . . . . . . X X O O . . O . |
$$ | . . . , . . . . X , . X O O . O O . O |
$$ | . . . . . . . . . X . O X X O . X O . |
$$ | . . . . . . . . . . X O X O 1 2 . X X |
$$ | . . . . . . . . . . C O . 3 . . . . . |
$$ ---------------------------------------[/go]


...now what?

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

Re: A life and death problem from my last game

Posted: Thu Oct 04, 2012 12:28 pm
by Samura
Hhhmm, after N1 the best I think black could do is to get a ko:

Click Here To Show Diagram Code
[go]$$Wc White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . X . X . . . . . . . |
$$ | . . . . . . . . . . . X X O O . . O . |
$$ | . . . , . . . . X , . X O O . O O . O |
$$ | . . . . . . . . . X . O X X O . X O . |
$$ | . . . . . . . . . . X O X 3 X O 2 X X |
$$ | . . . . . . . . . . C O 1 X . 4 . . . |
$$ ---------------------------------------[/go]