EVENT
BOARDSIZE 19
SETUP W E17 E18 E16 D16 C16 C15 B15 C11 D4 D6 K17 N17 R13 P12 P10 R10 S5 R4 R3 R2 Q2 O4 P4 P5 Q5 O6 G4 H3 K3 K2 L2 L4 M4 M3 N2 
SETUP B B17 C17 D17 B16 F17 C14 P17 Q16 R15 R12 Q12 Q13 R8 R6 S6 R5 P2 P3 Q3 Q4 O3 N3 N4 N5 M5 O5 N6 K5 K4 H5 F3 J2 H2 J3 
MARK \t@P12 \t@P10 \t@R10
COM
Problem 84. Black to play.  

How should Black attack the three marked stones ? 
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B 1 N12
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Capping with Black 1 is severe.
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  VAR
  B 1 P11
  COM
  Failure.

  If Black wedges in with 1, 
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  W 2 O10
  B 3 O11
  W 4 N10
  B 5 N11
  W 6 M10
  MARK \t@N17 \t@K17 5@N11 3@O11
  COM
  ... White easily escapes with the sequence to 6. The wall Black
  gets with 3 and 5 is ineffective because it is neutralised by
  the two marked stones at the top.
  <=
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  ENDVAR
W 2 N10
COM
If White 2, ...
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B 3 L11
COM
... Black continues the attack with the knight's move of 3.
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W 4 O12
COM
White tries to get some play with 4 ...
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B 5 N11
W 6 O14
COM
... and 6, but ...
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B 7 L16
COM
... Black leans on the White stones at the top with 7 ...
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W 8 Q14
B 9 R14
W 10 L17
B 11 N16
COM
... and 11. White is in trouble.
<=
ENDCOM