EVENT
BOARDSIZE 19
SETUP W C12 K17 M17 Q17 R17 R18 R15 R14 
SETUP B D17 C14 H17 O17 Q18 Q16 Q15 
MARK 2@R17 1@Q16
COM
Problem 100. Black to play.  

This time White solidly connects with 2 after Black 1. How does
Black respond ? 
ENDCOM
B 1 O15
MARK \t@Q15 \t@Q16 \t@Q18 \t@R18 \t@R17 \t@R15
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Again Black 1 is the vital point. Black's success can be measured
by the fact that his three marked stones have forced White to
make three submissive moves, shown by the three marked white
stones.
<=
ENDCOM
  VAR
  B 1 P17
  COM
  Failure.

  Of course, Black would like to play 1, ...
  ENDCOM
  W 2 O15
  COM
  ... but White would then hit him at the vital point of 2, destroying
  his shape.
  <=
  ENDCOM
  ENDVAR