EVENT
BOARDSIZE 19
SETUP W D16 D4 R14 R11 P11 D10 
SETUP B R16 P16 P14 P9 R9 Q4 
MARK A@N11 B@D10
COM
Problem 5. Black to play.  

Instead of jumping to A as in the "Correct Answer of Problem
1" , White plays B on the left side. How should Black attack
? 
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B 1 N11
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black attacks by capping with 1.
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W 2 O10
COM
White will run away with 2. Next, ...
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B 3 N8
COM
... Black plays the knight's move of 3, ...
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  VAR
  B 3 Q12
  MARK 2@O10 1@N11
  COM
  Failure.

  After exchanging 1 for White 2, Black could gauge out White's
  base and take some territory with 3 ...
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  W 4 Q11
  B 5 S13
  COM
  ... and 5. But Black loses the initiative in the center, and
  he is left with bad aji in the upper right corner.
  <=
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  ENDVAR
W 4 N10
B 5 L11
COM
... then jumps to 5. The white stones are in trouble. Next ...
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W 6 M11
COM
... White wedges in with 1, but, ...
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B 7 M12
W 8 M10
B 9 L12
W 10 L10
B 11 K10
W 12 K9
B 13 J10
W 14 L8
COM
... after the sequence to White 14, ...
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B 15 Q3
COM
... Black secures the lower right corner with 15.
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W 16 H9
COM
After White jumps to 16, ...
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B 17 K4
COM
... Black builds a moyo at the bottom with 17.
<=
ENDCOM