EVENT
BOARDSIZE 19
SETUP W D17 E17 C16 B14 B4 C6 C9 O3 Q2 L15 L14 N16 N15 M11 
SETUP B C3 D4 F3 Q4 R6 Q10 Q13 R16 Q16 P16 O16 N17 M17 L16 K15 F17 E16 G16 D14 K11 
MARK \t@M11 \t@L14 \t@L15 \t@N15 \t@N16
COM
Problem 47. Black to play.  

How should Black attack the marked white stones ? 
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B 1 N14
USER
CORRECT ANSWER
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COM
Correct Answer.

White 1 is the vital point, forcing White's stones into a bad
shape.
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  VAR
  B 1 L9
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  Failure.

  Black 1 looks like a severe attacking move, but it gives White
  the chance to counterattack.
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  W 2 P13
  MARK A@N14
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  She first plays a forcing move with 2, preventing Black from
  destroying her shape with A, ...
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  B 3 Q12
  W 4 K16
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  ... then cuts with 4. Next, ...
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  B 5 K17
  W 6 J16
  B 7 J17
  W 8 J14
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  ... White makes a wall with 8 ...
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  B 9 J15
  W 10 K14
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  ... and 10.
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  B 11 H15
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  After Black 11, ...
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  W 12 N9
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  ... White jumps to 12 and the two black stones in the center
  are isolated from their allies. As the Correct Answer of this
  problem illustrates, an important preliminary to attacking is
  to force your opponent's stones into a bad shape so that it is
  hard for her or him to make eyes.
  <=
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  ENDVAR
W 2 M14
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If White 2, ...
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  VAR
  W 2 O14
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  White 2 is an overplay.
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  B 3 M15
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  Black separates the white stones with 3 ...
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  W 4 O15
  B 5 M16
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  ... and 5.
  <=
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  ENDVAR
B 3 N13
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... Black extends to 3, ...
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W 4 L12
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... forcing White to defend with 4. The white stones are heavy
and open to an attack. See Problem 131.
<=
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