EVENT
BOARDSIZE 19
SETUP W D17 C4 C6 D3 E3 R6 R9 O17 L16 
SETUP B E4 F3 F4 K4 Q3 R4 R11 Q16 Q17 
MARK B@Q17 A@O17 C@L16
COM
Problem 11. Black to play.  

White has just extended to C. How should Black continue ? 
ENDCOM
B 1 P6
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.  

Black should cap at 1, ...  
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W 2 P9
COM
... forcing White to jump to 2.  
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B 3 P11
COM
This induces Black to reinforce his moyo above with 3.  
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W 4 N9
COM
Jumping to 4 is natural.  
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B 5 J17
COM
Black now invades the top with 5.  
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W 6 G17
COM
White has to play forcefully and pincer with 6.  
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  VAR
  W 6 K15
  MARK 5@J17
  COM
  Variation.  

  White 6 here is another response to Black 5.  
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  B 7 H15
  COM
  Black jumps to 7 and ...  
  ENDCOM
  W 8 G17
  COM
  ... White pincers with 8.  
  ENDCOM
  B 9 G16
  W 10 F17
  B 11 H17
  MARK 9@G16
  COM
  Black makes shape with 9 and 11, after which ...  
  ENDCOM
  W 12 D15
  B 13 J13
  W 14 L13
  B 15 J11
  MARK 13@J13
  COM
  ... Black attacks with 13 and 15.  
  ENDCOM
  W 16 L11
  COM
  After White 16, ...  
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    VAR
    W 16 O15
    COM
    If White 12 here, ...  
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    B 17 P14
    COM
    ... Black will play 17 here.  <= 
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    ENDVAR
  B 17 O15
  COM
  ... Black secures the territory on the right with 17.  <= 
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  ENDVAR
B 7 J15
W 8 K17
COM
If White attaches with 8, ...  
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B 9 K18
W 10 L18
B 11 K16
W 12 L17
B 13 L15
W 14 M15
B 15 L14
W 16 M14
B 17 M13
COM
... Black presses the white stones with the sequence to 17.
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W 18 O15
COM
White then makes shape with 18 and ...  
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B 19 P14
COM
... Black secures the upper right with 19.  <= 
ENDCOM