EVENT
BOARDSIZE 19
SETUP W C14 C11 J17 J15 O17 O16 
SETUP B C16 D16 G17 G15 P17 Q16 Q14 
MARK \t@J15 \t@G15
COM
Problem 24.  Black to play.  

White and Black have exchanged the marked stones. Where is Black's
invasion point now ? 
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B 1 K16
USER
CORRECT ANSWER
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COM
Correct Answer.

Black should first peep at 1, ...
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  VAR
  B 1 L17
  COM
  Failure.

  Invading deeply at 1 could be disastrous for Black ...
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  W 2 L15
  COM
  ... after White caps with 2.
  <=
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  ENDVAR
W 2 J16
B 3 M16
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... then play on the vital point of 3.
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W 4 O14
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When White jumps to 4, ...
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B 5 M14
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... Black jumps to 5. Black can now attach on either the left
or the right.
<=
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