EVENT
BOARDSIZE 19
SETUP W D16 D10 D4 K16 O17 
SETUP B Q16 Q14 Q9 Q3 K4 
MARK 1@D10
COM
Problem 63. Black to play.  

White concentrates on building her own moyo by making a sanren-sei
with 1, ignoring what Black might do next. How should Black play
? 
ENDCOM
B 1 F3
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black should approach with 1, ...
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  VAR
  B 1 C14
  COM
  Failure.

  In this kind of position, Black must never make an approach move
inside White's sphere of influence, ...
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  W 2 C15
  COM
  ... for he will come under a severe attack with the sequence
  from 2 ...
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  B 3 D14
  W 4 F16
  B 5 D12
  W 6 C11
  COM
  ... to 6.
  <=
  ENDCOM
  ENDVAR
W 2 D6
COM
... then, when White answers with 2, ...
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B 3 P4
MARK A@Q5
COM
... strengthen his corner with 3 or A. Black has taken the initiative
and is on the road to victory.
<=
ENDCOM