EVENT
BOARDSIZE 19
SETUP W D17 D15 H17 H15 C10 R17 
SETUP B K17 K15 Q16 Q10 
MARK 1@R17
COM
Problem 77. Black to play.  

Invading at 1, the 3-3 point, when Black has a stone on the star
point, is usually the vital point. In which direction should
Black play ? 
ENDCOM
B 1 Q17
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black should block at 2 ...
ENDCOM
  VAR
  B 1 R16
  COM
  Failure.

  Blocking from this side with 1 ...
  ENDCOM
  W 2 Q17
  B 3 P17
  W 4 P18
  B 5 O17
  W 6 O18
  B 7 N17
  W 8 S16
  B 9 S15
  W 10 S17
  B 11 R14
  MARK \t@K15 \t@K17
  COM
  ... results in the joseki up to 11, but it leaves Black with
  a shallow moyo.
  <=
  ENDCOM
  ENDVAR
W 2 R16
B 3 Q15
MARK \t@K15 \t@K17
COM
... and extend to 3 to make a box-like territory on the left.
<=
ENDCOM