EVENT
BOARDSIZE 19
SETUP W C16 C15 D17 F17 D4 C6 C3 C2 K4 L5 L4 L3 N3 R10 Q12 R14 S14 S15 
SETUP B D15 D14 C14 D10 C8 D2 F3 H4 K3 J3 M4 P3 R4 Q6 R8 R15 S16 Q16 O16 
MARK B@R17 A@M17 C@F15
COM
Problem 137. White to play.  

After Black plays the marked stone, the only interesting points
remaining are at the top. Does White have any special stratagem
at B or is there something else she should do ? 
ENDCOM
W 1 M17
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

There are no special tricks that White can pull off in the corner,
so it is best for her to play 1, ...
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  VAR
  W 1 F15
  COM
  Failure.

  A move like 1 does nothing to improve White's position.
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  B 2 L17
  MARK B@R16 A@R17
  COM
  Black 2 strengthens his weak stones at the top and takes profit
  besides. If White now peeps at A, Black simply connects at B
  and the stone at A is lost.
  <=
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  ENDVAR
B 2 O17
COM
... forcing Black to defend at 2.
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W 3 J16
COM
She can take up a position on the top with 3. The middle game
now begins.
<=
ENDCOM