EVENT
BOARDSIZE 19
SETUP W D17 H16 D11 D6 D4 Q3 R3 O3 O2 
SETUP B K16 Q16 Q10 G4 M3 N5 P4 Q4 R4 
COM
Problem 50. Black to play.  

White has countered Black's sanren-sei opening with a Chinese
opening. Where should Black play ? 
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B 1 J14
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black 1 is the focal point of the two moyos.
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  VAR
  B 1 G7
  COM
  Failure.

  Black 1 is also a good point because it strengthens his thin
  position at the bottom. However, ...
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  W 2 J14
  COM
  ... White takes the vital point of 2 and ...
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  B 3 L14
  W 4 K12
  COM
  ... marches into Black's sphere of influence with 4.
  <=
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  ENDVAR
W 2 G14
COM
If White defends her moyo with 2, ...
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B 3 H12
COM
... Black keeps advancing with 3, making the scale of his moyo
even greater while diminishing the scale of White's.
<=
ENDCOM