Simple connection question

PeterPeter · Post by **PeterPeter** » Fri Oct 05, 2012 11:54 am

Click Here To Show Diagram Code: [go]$$Wc $$ +-------------------+ $$ | . . . . . . . . . | $$ | . . . . . O X . . | $$ | . . O . O . X . . | $$ | . . . . . . . . . | $$ | . . O . X . X . . | $$ | . O . . . . . . . | $$ | . . X b X . X . . | $$ | . O X a . . . . . | $$ | . O O Y . . . . . | $$ +-------------------+[/go]

I want to protect the marked Black stone. The computer is suggesting A, but I feel that B is better as it is closer to the important centre. Any thoughts?

Horibe · Post by **Horibe** » Fri Oct 05, 2012 11:59 am

Your thinking is not bad, but the answer is b3

jts · Post by **jts** » Fri Oct 05, 2012 12:00 pm

B3 is best. If you need to connect, connecting by capturing enemy stones is always preferable to playing inside your territory.

As for d2 versus d3... this is a matter of taste and circumstance. The question comes up a lot. D3 is a "hanging connection". It normally stretches out further to affect points further away, but it leaves ko threats (the atari at e1), peeps (at e2), and various other weaknesses that the the "direct" or "solid" connection at d2 doesn't have.

p2501 · Post by **p2501** » Fri Oct 05, 2012 12:01 pm

b) helps more in the center but also leaves a ko threat at the bottom.

If a) or b) would make no difference in territory, a) would be clearly better.

PeterPeter · Post by **PeterPeter** » Fri Oct 05, 2012 12:09 pm

I did look briefly at b3, and rejected it due to White connecting on a3, but I have now seen that Black can play a2 and win the corner through a snapback!

Bill Spight · Post by **Bill Spight** » Fri Oct 05, 2012 1:36 pm

Horibe wrote:Your thinking is not bad, but the answer is b3

Is that one of those "basics"?

jts · Post by **jts** » Fri Oct 05, 2012 2:29 pm

PeterPeter wrote:I did look briefly at b3, and rejected it due to White connecting on a3, but I have now seen that Black can play a2 and win the corner through a snapback!

Yes, but knowing the answer, it might be fun for you to read through it to make sure. It's a good readin exercise.

Bonobo · Post by **Bonobo** » Fri Oct 05, 2012 2:37 pm

Bill Spight wrote:
Horibe wrote:Your thinking is not bad, but the answer is b3

Is that one of those "basics"?

Since this was also what I thought, it must be totally basic

fundamentally, essentially basic.

jts · Post by **jts** » Mon Oct 08, 2012 12:32 pm

Another connection problem. B is a mess - four cutting points, no less. What's the best way for B to connect?

Click Here To Show Diagram Code: [go]$$B Corner $$ ------------------ $$ | . . X . O . . . . $$ | . O O X O X C . . $$ | . O X O O O X . . $$ | . . X X O X C . . $$ | . . . C X C . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . .[/go]

PeterPeter · Post by **PeterPeter** » Mon Oct 08, 2012 1:11 pm

This protects 2 of the cutting points with one stone:

Click Here To Show Diagram Code: [go]$$B Corner $$ ------------------ $$ | . . X . O . . . . $$ | . O O X O X C . . $$ | . O X O O O X . . $$ | . . X X O X C . . $$ | . . . C X C B . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . .[/go]

Or you could occupy one and protect the other using a ladder:

Click Here To Show Diagram Code: [go]$$B Corner $$ ------------------ $$ | . . X . O . . . . $$ | . O O X O X C . . $$ | . O X O O O X . . $$ | . . X X O X B . . $$ | . . . C X C . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . .[/go]

There are a few places to set up a similar ladder, you would choose one based on the rest of the board?

EdLee · Post by **EdLee** » Mon Oct 08, 2012 1:17 pm

Peter,

PeterPeter · Post by **PeterPeter** » Mon Oct 08, 2012 1:29 pm

1. Oh yes, you can win the white group

2. Not as good as winning the group, but the ladders at A and B look OK, as far as we can see of the board?

Click Here To Show Diagram Code: [go]$$B $$ ------------------ $$ | . . X . O . . . . $$ | . O O X O X . . . $$ | . O X O O O X . . $$ | . . X X O X . . . $$ | . . . a X b . . . $$ | . . . . B . . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . .[/go]

EdLee · Post by **EdLee** » Mon Oct 08, 2012 1:34 pm

PeterPeter wrote:2. Not as good as winning the group, but the ladders at A and B look OK, as far as we can see of the board?
$$W
$$ ------------------
$$ | . . X . O . . . .
$$ | . O O X O Y 1 . .
$$ | . O X O O O X . .
$$ | . . X X O X . . .
$$ | . . . a X b . . .
$$ | . . c . B . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .

Click Here To Show Diagram Code
[go]$$W $$ ------------------ $$ | . . X . O . . . . $$ | . O O X O Y 1 . . $$ | . O X O O O X . . $$ | . . X X O X . . . $$ | . . . a X b . . . $$ | . . c . B . . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . .[/go]

W can kill :bt:

with

IN SENTE, and B still has to deal with all his weaknesses.
(For example, if the situation changes later, a local vital point for W to annoy B is (c).)

jts · Post by **jts** » Mon Oct 08, 2012 2:03 pm

PeterPeter wrote:Not as good as winning the group, but the ladders at A and B look OK, as far as we can see of the board?

No, those ladders/nets/whatever look painful.

I'd rather capture!

Have you seen a ladder breaker played? In most problems we don't show the other corners, but we know that ladders are really painful so a solution with a ladder is worse than a solution without a ladder. (Likewise, we don't show ko threats in most games, but if you've fought through a lot of kos you know that an unconditional solution is always much better than a ko, and making a ko is better than a kick in the face.)

xed_over · Post by **xed_over** » Mon Oct 08, 2012 3:05 pm

jts wrote:making a ko is better than a kick in the face.

hahaha... someone needs to take this as their sig.

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