EVENT
BOARDSIZE 19
SETUP W K17 L16 Q17 P16 R15 R10 
SETUP B C16 E17 H17 M17 P17 
MARK 1@P16
COM
Problem 81. Black to play.  

How should Black answer the hane of White 1 ? 
ENDCOM
B 1 Q18
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

The hane of Black 1 is the best response.
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  VAR
  B 1 O17
  COM
  Failure.

  If Black immediately draws back with 1 here, ...
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  W 2 Q18
  COM
  ... White will descend to 2.
  ENDCOM
  B 3 N15
  COM
  This result is better for White than the one in the Correct Answer.
  <=
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  ENDVAR
W 2 Q16
COM
After White connects at 2, ...
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B 3 O17
W 4 R18
B 5 N15
MARK 3@O17
COM
... Black makes shape with 3 and 5.
<=
ENDCOM