EVENT
BOARDSIZE 19
SETUP W D16 N17 P17 R18 Q4 
SETUP B L16 R16 Q14 R10 E3 C4 
MARK B@C10 A@J16 C@R8 D@K3
COM
Problem 142. White to play.  

A joseki has just been played out in the upper right. How should
White continue ? Should she play an attacking move or should
she be satisfied just making a big point ? 
ENDCOM
W 1 C10
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

White should extend to 1, limiting the influence of Black's corner
enclosure.
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  VAR
  W 1 K3
  COM
  Failure.

  White 1 is not good ...
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  B 2 C10
  MARK C@R8 1@K3 A@J16
  COM
  ... because Black can make an ideal extension from his corner
  enclosure with 2. White A or C are the next biggest points, but
  1 and 2 take priority because no stones have been played in these
  areas yet.
  <=
  ENDCOM
  ENDVAR
B 2 O3
W 3 R6
B 4 C8
  VAR
  B 4 K4
  MARK @@C8
  COM
  If White neglects to play 4 at @ and plays 4 here instead, ...
  ENDCOM
  W 5 C7
  COM
  ... White will extend down the left side.
  <=
  ENDCOM
  ENDVAR
W 5 P3
B 6 O4
W 7 K4
COM
The game continued with the sequence to White 7.
<=
ENDCOM