EVENT
BOARDSIZE 19
SETUP W D17 C16 C15 Q3 R3 O3 E4 
SETUP B C14 D15 G14 Q16 Q10 Q4 R4 P5 
MARK B@C4 C@N4 A@Q14
COM
Problem 116. Black to play.  

Black has played lightly in the upper left, so his stones should
encounter no problems and he can leave them as they are. Which
of the three points indicated would you play ? 
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B 1 N4
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black 1 is the vital point.
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  VAR
  B 1 Q14
  COM
  Failure.

  If Black strengthens his position in the upper right with 1,
  ...
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  W 2 O5
  COM
  ... White will play 2 ...
  ENDCOM
  B 3 O6
  W 4 N5
  COM
  ... and 4, reducing the scale of Black's moyo on the right.
  ENDCOM
  B 5 C4
  COM
  If Black now approaches at 5, ...
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  W 6 D6
  COM
  ... White gets the advantage when she plays 6.
  <=
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  ENDVAR
W 2 O4
COM
White cuts through with 2 ...
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  VAR
  W 2 N3
  COM
  Variation.

  If White crawls to 2, ...
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  B 3 M4
  COM
  ... Black will extend to 3 and make a moyo in the center.
  <=
  ENDCOM
  ENDVAR
B 3 O5
W 4 N5
COM
... and 4, ...
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B 5 L4
W 6 N6
B 7 N3
W 8 N2
B 9 M2
W 10 O2
B 11 L6
W 12 N8
B 13 Q8
MARK \t@G14
COM
... and the joseki to 13 follows. The marked stone will have
an influence on the ensuing fight.
<=
ENDCOM