EVENT
BOARDSIZE 19
SETUP W C10 D17 F16 M17 R10 R6 Q6 Q5 E4 C5 
SETUP B B17 C15 C12 O17 R16 R13 R5 R4 Q3 O3 
COM
Problem 103. Black to play.  

Black and White have established positions in all four corners
and on the sides. All of Black's positions are strong, so Black
should now go on the offensive. Where should he play ? 
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B 1 J16
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Since White's position at the top is thin and Black has strong
positions on the left and the right, Black should seize the initiative
by invading at 1.
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  VAR
  B 1 G3
  COM
  Failure.

  The checking extension of Black 1 is certainly a good move, but,
with respect to the whole board, it is not the focal point of
  the game.
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  W 2 J16
  COM
  White will defend the top with 2 and Black has lost his chance
  to take the decisive lead as in the Correct Answer diagram.
  <=
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  ENDVAR
W 2 M15
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After the exchange of 2 ...
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B 3 J14
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... for 3, White is left with weak stones on the left and on
the right. Black has taken the lead.
<=
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