EVENT
BOARDSIZE 19
SETUP W C12 K17 Q17 R14 P15 
SETUP B D17 C14 H17 O17 
MARK 2@P15 1@O17
COM
Problem 79. Black to play.  

Suppose White answers the invasion of Black 1 with 2. How does
Black continue ? 
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B 1 O15
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black exchanges 1 ...
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W 2 P14
COM
... for 2, ...
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  VAR
  W 2 O14
  MARK 1@O15
  COM
  Variation.

  White could answer 1 with 2 ...
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  B 3 N15
  W 4 K15
  COM
  ... and jump to 4.
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  B 5 P16
  COM
  Black would then play 5, ...
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  W 6 Q16
  COM
  ... followed by White 6.
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    VAR
    W 6 Q15
    MARK 5@P16
    COM
    White could also answer 5 with 6 here, but her shape in this
    corner is full of holes.
    <=
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    ENDVAR
  B 7 P14
  COM
  If the ladder is favourable, Black would atari at 7 ...
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  W 8 Q15
  B 9 O13
  COM
  ... and 9.
  <=
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  ENDVAR
B 3 K15
COM
... then caps with 3. Black's moves flow very beautifully.
<=
ENDCOM