EVENT
BOARDSIZE 19
SETUP W C16 J17 O17 O16 O15 O13 Q12 M11 
SETUP B J15 M15 M17 P17 Q16 Q14 S15 D4 Q4 
MARK \t@J17
COM
Problem 75. Black to play.  

How should Black attack the marked white stone at the top ? 
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B 1 H17
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black's three stones are thin, so he should strengthen them by
attacking the white stone at the top.
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W 2 H18
  VAR
  W 2 H16
  COM
  Variation.

  If White hanes on the outside with 2, ...
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  B 3 J16
  COM
  ... Black cuts with 3. White's stones are too week to fight and
  ...
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  W 4 G17
  B 5 H18
  W 6 J18
  B 7 G18
  COM
  ... her position collapses after Black 7.
  <=
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  ENDVAR
  VAR
  W 2 J16
  COM
  Variation.

  White might play 2 here ...
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  B 3 H16
  W 4 K15
  COM
  ... and 4, but ...
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  B 5 K16
  COM
  ... Black cuts with 5.
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  W 6 L16
  COM
  If White sacrifices two stones by playing 6 ...
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    VAR
    W 6 H18
    MARK 5@K16
    COM
    If Black cuts at 5, White can't hane at 6.
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    B 7 J18
    W 8 K17
    B 9 K18
    W 10 L16
    B 11 L17
    W 12 K16
    B 13 K14
    W 14 J14
    B 15 H15
    W 16 L14
    B 17 K13
    W 18 L15
    B 19 L13
    COM
    Black squeezes with the sequence to 19, then ...
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    W 20 M14
    B 21 F17
    COM
    ... settles his stones at the top by jumping to 21.
    <=
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    ENDVAR
  B 7 K17
  W 8 L17
  COM
  ... and 8, ...
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  B 9 J18
  MARK B@L18 A@L15
  COM
  ... Black captures with 9 and dominates the top. Next, the points
  A and B are miai.
  <=
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  ENDVAR
B 3 H16
W 4 G18
B 5 E16
W 6 F17
B 7 F16
W 8 D17
COM
The sequence to 8 is the best both sides can hope for.
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B 9 D14
COM
Finally, Black plays 9 and he has built a wall that will later
be effective in attacking the six white stones in the top right.
Next ...
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W 10 Q6
COM
The game continued with White mapping out a moyo on the right
side with 10 ...
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B 11 O4
W 12 O6
COM
... and 12.
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B 13 M4
W 14 C6
B 15 D9
W 16 F3
B 17 D6
W 18 C3
B 19 C5
W 20 D3
B 21 B6
W 22 B14
COM
After the joseki in the lower left corner, White slides to 22
to prevent Black from making territory on the left side. See
Problem 130.
<=
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