The Game of Go

[Vinny]

The Original Problem

Originally posted by casinopete:

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Black to Live:

Go Board

---

White Black

---

---

So all the young hopeful who haven't been burnt can try and not have to go flip back a page.


My attempt:

b A3, w A2
b A4, w C2
b D3, w B1
b C1, w B2
b A1 X, w B2
b B3, w C2

Go Board

---

White Black

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Black have eyes at B2 and C3 at this point (NOT!). Unless pete pull something else out of his butt ...

OH wait ! pah! (he did!)

So yeah, my solution is shot. Darn you Pete! Darn you to heck!




[This message has been edited by Vinny (edited 05-09-2004 08:28 AM).]

[casinopete]

b A3, w A2, b A4, w C2, b D3, w B1 has us here:

Black to Live:

Go Board

---

White Black

---

Black has to C1, or white will, giving white two eyes. Then white will fill in B2.

Black to Live:

Go Board

---

White Black

---

White will eventually fill in the liberties around black, and black will have to capture at A1, and then white will refill B2:

Black to Live:

Go Board

---

White Black

---

And black cannot get more than one eye.

(There's a reason I mentioned nadakes before posting this problem) fnord.

[casinopete]

Bah. You posted too quickly. C3 is not an eye, though.

[Vinny]

I give up.

[casinopete]

The key ideas for this last problem aren't really very complex, though the moves themselves are quite tricky. As Antrax said, black's almost certainly gonna have to kill white, which means the first order of business is going to have to be cutting off white's ability to connect "underneath" with A4.

There's a second consideration to keep in mind, though - white's ability to cut at D3. Black can't just fill, since he needs to keep white from connecting - so he needs to prepare for white's cut. Now, after cutting, white will have 3 liberties to black's two, so black needs to make sure his first move either takes away one of white's liberties, or gains one for himself.

A3 fits both requirements, and was the first move to pop into my mind when I first saw the problem. Of course, as Vinny and I showed by playing it out (which was the exact sequence I envisioned while trying to work out the answer)... it doesn't quite work because of the tricky nadake shape.

The other "obvious" moves to check are A4 and B2, but B2 fails to cut white off, and A4 fails to help with the liberty situation - so we have to be a bit sneakier. The correct starting move is actually... A2!

If white plays A3 to threaten to connect, black could safely block him in with A4 - white doesn't have the liberties to D3, and black's stone at A2, though it would get captured, would keep white from building the nadake shape in the variation Vinny and I played out.

If white tries C2, black just fixes D3, and there's nothing more for white to do. Black also has an easy answer to B2 - just A3.

That leaves only the cut at D3 for white, which looks very strong, and is why this problem is actually a difficult one. Black's next answer involves the initial logic in the problem. A2 obviously stopped white's connection, but it didn't seem to do anything about the relative liberties after white's cut. The truth is, it gives black extra liberties by virtue of a sneaky second move... B1!

situation:
Go Board

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White Black

---

From here, knowing the correct first two moves, it's obvious that they have worked. If white tries A3, black just A4, and white is short of liberties, so black can capture whenever he wishes. B2 is also an obvious failure, as black's A3 answer would put white in atari.

If anyone is interested in more problems, I can continue providing them - maybe every day or two, depending on my access situation.

[Vinny]

wow!

I need to study this again when I am more alert. That's a tricky problem indeed!

Say, what would happened if after Black played at A2, White then played at A4? Wouldn't that pretty much connect White group at B3 to B5 and to the outer group, as I have said to Antrax?

[casinopete]

If black A2, white A4, black can just A3. It puts A4 in atari, and cuts white's liberties by one. If white connects at A5, black lives easily with B2, if white plays D3, black plays the same B1 answer as in the other sequence, and anything else white can do is countered by black playing either A5 (capturing A4) or D3 himself.

[Vinny]

Ah. It's so frigging obvious now. Haha!

More problem please. Maybe a killing problem this time?

[casinopete]

Your wish is my command.

Black to Kill:

Go Board

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White Black

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[Vinny]

[I5]?

[casinopete]

black I5, white A6

[Vinny]

[
White A6??!??! Do you mean, I6?

if Whit I6

b I5, w I6
b I7 (take)
]

[casinopete]

oops. Yes, I meant i6.

b i5, w i6
b i7, w i8

[Vinny]

Ah, I see, White would make the eyes eventually with corner posititon I9 and H8.

Hmmm...

[Vinny]

since this is the case, I am thinking [ black I7]

[This message has been edited by Vinny (edited 05-14-2004 12:51 AM).]

[casinopete]

black i7, white i6

[Vinny]

I hate you.

[I8] then?

Hahhahahahahhaha.

[casinopete]

black i8, I believe still white i6

[casinopete]

Here's a little go proverb that may be of assistance:

"Your opponent's best move is often your best move."

fnord.

[Vinny]

gee, thanks.

[Black I6] first then.



[This message has been edited by Vinny (edited 05-15-2004 01:29 AM).]

[casinopete]

black i6, white i7

[Vinny]

[
b i6, w i7
b h7
]
?

[casinopete]

black i6, white i7
black h7, white i5

[Vinny]

Go Board

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White Black

---

black i6, white i7
black h7, white i5

so why can't black h8?

Eventually, white I7 to I9 is taken. Wouldn't that guarantee white group death for the white group at F and G?

[casinopete]

He can.
I erred.

white H8 instead of I5.

[Vinny]

Black to Kill:

[Vinny]

ooo oooo, I think I see it.

Black i7, then h9 or i8

[Vinny]

this thread is ruined

[Antrax]

It'll be restored to its prime soon enough. Don't worry.
Antrax
_________________
After years of disappointment with get rich quick schemes, I know I'm gonna get rich with this scheme. And quick!

[Antrax]

Told you (I re-uploaded the pictures).
Still no tags, though. Go bug Hy
Antrax
_________________
After years of disappointment with get rich quick schemes, I know I'm gonna get rich with this scheme. And quick!

[Vinny]

Heck, I'll write it myself. Give me access to the php, baby!!!

[Vinny]