OD1P - May 22 Problem / Solution

Black To Play  

.. a at ^[1]

...b at ^[2]

...c at ^[3]

...d at ^[4]

...e at ^[5]

...f at ^[6] (Correct solution)

Black fails  

White connects, main black group is dead even if the three stones on left might escape.

Mistake  

Black has no continuation here

Black plays at Q18  

Q18, Black dies in failure.

Black Start  

Black lives only if White plays this sequence follishly to allowing Blace to capture at a. White can play b as , , , or even to connect to White's two stones and thus kill the main Black group even if allowing Black's few stones on left to escape if they can. The longer White delays in playing b after , the better for Black.

Black Start  

signal9: I'm not 100% sure, but this looks pretty good to me.

Black Start  

unkx80: Nah... this is a failure diagram.

Order?  

YongCao? I think should play first, then .

Black Dies  

PeiweiCao? Black dies:

Main line  

If White comes from the inside with , she can't capture because of the snapback. The successive throw-in of qnd are the tesuji here.

Variation  

If White comes from the other side, forces to capture, then connects at . This is more straightforward than the main line.

Main line (bis)  

Adding the - exchange doesn't fundamentally alter the main line.

Whites's throw-in  

Likewise exchanging - doesn't change the solution. connects at and then we're again at either a (main line) or b (variation)