Beginner Exercise 112 / Solution

White wins  

Confused: increases the liberties to three for the white group; and after Black needs an additional approach move at before being able to play at a.

Variation: this is not a ko  

Variation: black might play trying to start a ko, but white still wins the capturing race ( at , at a).

Variation: Black trying to escape  

Variation: black might try to escape to the right. In that case white can stop him with the following sequence. A potential cut at a could be easily fended off by playing at b and putting the black group into atari.

Variation: white falls for a trick  

With , black tries to set up a ko. is a mistake.

Variation: no ko  

After this , the variations get a little complicated, but white can kill without ko. (Black is trying to set up something like a tombstone squeeze, but it doesn't work in this context.)

Seki  

A seki isn't a good result, when White can kill instead.

Death for White  

If Black is allowed to play at , the white group dies. It doesn't matter whether White played at or at a, b, c or d.