EVENT
BOARDSIZE 19
SETUP W C18 D18 E17 E16 D16 C16 C13 H4 J4 G3 G1 H2 F2 E2 D2 D3 E3 C3 R4 S3 T4 S5 Q5 R6 R10 O17 O16 P18 Q18 Q17 R17 S18 T18 
SETUP B C17 D17 E18 F19 F17 G18 J17 C10 D1 C2 B3 C4 D4 E4 F4 F3 G4 H5 O3 Q3 Q4 R3 R12 S17 T16 S15 R16 Q16 P16 P17 N17 N18 O18 
MARK \t@O16 \t@O17
COM
Problem 82. Black to play.  

What should Black do about the two marked stones ? Should he
capture them in a ladder or is there something else he can do
? 
ENDCOM
B 1 Q10
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black 1 and ...
ENDCOM
  VAR
  B 1 O15
  COM
  Failure.

  Black captures the two white stones in a ladder, but ...
  ENDCOM
  W 2 C8
  COM
  ... White counters with an invasion at 2. This move also blocks
  the ladder, so the fighting can become quite complicated.
  <=
  ENDCOM
  ENDVAR
  VAR
  B 1 E10
  MARK A@C8
  COM
  Failure.

  Black 1 prevents the invasion at A and, if you lack confidence
  in fighting, this is also a good move. But, compared to the Correct
  Answer, it is a bit slack.
  <=
  ENDCOM
  ENDVAR
W 2 R9
B 3 R11
MARK A@O15
COM
... 3 are moves which take the whole board into account. Capturing
the two stones in a ladder with A is small in scale. Next ...
ENDCOM
W 4 P11
COM
White counterattacks with the peep of 4, then ...
ENDCOM
B 5 Q11
W 6 N16
B 7 M16
W 8 M15
B 9 L16
W 10 N14
MARK 8@M15
COM
... extracts her stones at the top with 8 to 10. Next ...
ENDCOM
B 11 M13
COM
Black attacks the four white stones with 11 and ...
ENDCOM
W 12 L15
B 13 K13
COM
... 13, then, ...
ENDCOM
W 14 J15
COM
... after White jumps to 14, ...
ENDCOM
B 15 B17
COM
... plays the sequence from 15 ...
ENDCOM
W 16 B18
B 17 B16
W 18 B15
B 19 C15
COM
... to 19 to create aji in the upper right corner. Next ...
ENDCOM
W 20 A17
B 21 H13
COM
Black continues the attack ...
ENDCOM
W 22 G15
B 23 F16
W 24 F15
B 25 F13
W 26 E14
B 27 D12
COM
... with the sequence to 27, mapping out a large moyo on the
left side.
<=
ENDCOM