EVENT
BOARDSIZE 19
SETUP W C16 E16 H17 C12 R14 Q14 R11 R17 
SETUP B K17 C10 O16 Q16 R16 R15 
MARK 2@R16 1@R17
COM
Problem 138. White to play.  

How does White respond to Black 2 ? 
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W 1 Q18
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

The diagonal move of 1 gives White good shape.
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  VAR
  W 1 Q17
  COM
  Failure.

  White 1 is a bad move.
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  B 2 P17
  COM
  Black plays 2 and gets a solid shape.
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  W 3 S16
  COM
  After this, White must play 3, ...
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  B 4 S15
  W 5 S18
  B 6 T16
  W 7 T17
  COM
  ... and she can only live in the corner by winning a ko.
  <=
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  ENDVAR
B 2 Q17
COM
If Black 2, ...
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W 3 S18
COM
... White plays 3, easily making life in the corner.
<=
ENDCOM