EVENT
BOARDSIZE 19
SETUP W D17 D14 H16 O3 K4 D4 D3 D5 E7 C8 
SETUP B K16 K14 O17 Q16 Q4 Q6 B6 C6 C4 C3 Q10 
MARK A@H14 B@E9 C@O5 D@Q2
COM
Problem 146. White to play.  

This is another contest of moyos. Where is the crucial point
for White to play in this position ? 
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W 1 O5
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

White 1 is the biggest point.
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  VAR
  W 1 H14
  COM
  Failure.

  White 1 is too narrow. The bottom is bigger, ...
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  B 2 M5
  COM
  ... so Black will jump out to 2.
  <=
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  ENDVAR
  VAR
  W 1 E9
  COM
  Failure.

  Only a defensive move.
  <=
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  ENDVAR
  VAR
  W 1 Q2
  COM
  Failure.

  White 1 here only seeks territory.
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  B 2 M5
  COM
  Black will ignore it and jump to 2.
  <=
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  ENDVAR
B 2 O7
COM
If Black caps with 2, ...
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W 3 R12
COM
... White will switch to 3. She should have no trouble making
a living group there.
<=
ENDCOM