EVENT
BOARDSIZE 19
SETUP W D16 D4 D6 R17 S16 P18 R14 Q14 Q13 Q12 O13 R11 R10 P10 
SETUP B F4 N3 Q4 R8 L17 Q16 O16 R15 S15 S14 R13 R12 P11 Q11 
COM
Problem 68. Black to play.  

How should Black attack the white stones on the right ? 
ENDCOM
B 1 O10
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black 1 ...
ENDCOM
  VAR
  B 1 O11
  COM
  Correct Answer.

  Extending to Black 1 is the standard way to attack.
  ENDCOM
  W 2 Q10
  COM
  After White defends with 2, ...
  ENDCOM
  B 3 P8
  COM
  ... Black jumps to 3. Again, White is split into two groups;
  if she tries to save the one on the right side, her group above
  will die.
  <=
  ENDCOM
  ENDVAR
  VAR
  B 1 N11
  COM
  Failure.

  Black 1 is bad.
  ENDCOM
  W 2 Q8
  COM
  White can now exchange 2 ...
  ENDCOM
  B 3 R7
  COM
  ... for 3, ...
  ENDCOM
  W 4 O11
  COM
  ... then wedge in at 4.
  ENDCOM
  B 5 O10
  COM
  If Black ataris with 5, ...
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    VAR
    B 5 O12
    COM
    Black might atari from above with 5.
    ENDCOM
    W 6 O10
    B 7 P12
    COM
    After Black connects at 7, ...
    ENDCOM
    W 8 P15
    COM
    ... White peeps at 8, ...
    ENDCOM
    B 9 P16
    W 10 N12
    COM
    ... then blocks with 10 and ...
    ENDCOM
    B 11 N13
    W 12 M12
    B 13 P13
    W 14 O14
    COM
    ... the black stones are trapped.
    <=
    ENDCOM
    ENDVAR
  W 6 O12
  COM
  ... White extends to 6, and, ...
  ENDCOM
  B 7 Q10
  W 8 P9
  COM
  ... after White 8, the three black stones are trapped.
  <=
  ENDCOM
  ENDVAR
W 2 Q10
COM
... forces White to connect at 2.
ENDCOM
B 3 N11
MARK A@P8 B@M13
COM
Black then plays 3 and the points A and B are miai. Whichever
way White plays, she will lose some stones.
<=
ENDCOM