EVENT
BOARDSIZE 19
SETUP W C15 C3 Q4 S17 R17 Q16 R15 P16 O15 O18 O17 
SETUP B R16 O16 N16 N17 N18 P17 P18 Q17 R18 
COM
Problem 93. Black to play.  

Black has made a thick position in the top right. He must now
prevent White from making a corner enclosure in the upper left.
How should Black approach the white stone there ? 
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B 1 E16
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

The high approach of Black 1 works best with Black's thick position
in the upper right.
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  VAR
  B 1 D17
  COM
  Failure.

  The usual approach move at 1 is not good.
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  W 2 E16
  COM
  White presses Black in a low position with 2 ...
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  B 3 E17
  W 4 F16
  COM
  ... and 4.
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  B 5 G17
  COM
  After 5, ...
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  W 6 D10
  MARK A@G16
  COM
  ... White can map out a moyo on the left side with 6 or she can
  continue to press the black stones with A.
  <=
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  ENDVAR
W 2 D17
B 3 E17
W 4 D16
B 5 E15
W 6 D14
B 7 F13
COM
Even though White gets the territory in the corner, Black maps
out a moyo at the top with the sequence to 7.
<=
ENDCOM