EVENT
BOARDSIZE 19
SETUP W D16 C15 D15 D14 G16 G14 H14 K15 F12 C9 E9 G9 Q3 R6 
SETUP B C14 D13 E13 E14 G13 H13 J13 E11 F11 C7 C4 E3 R16 P17 
COM
Problem 90. Black to play.  

The white stones on the left are thin. How can Black attack them
while strengthening his own stones ? 
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B 1 F8
USER
CORRECT ANSWER
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COM
Correct Answer.

Since the Black stones are not at all that secure themselves,
Black should first peep at 1, then, ...
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W 2 F9
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... after White connects with 2, ...
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B 3 J9
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... cap with 3. White's stones are in danger, so she has to scramble
to make life on the left side.
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W 4 D7
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White now attaches with 4.
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B 5 D6
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After exchanging 5 ...
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W 6 E7
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... for White 6, ...
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B 7 C8
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... Black bumps against the white stone with 7. Next ...
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W 8 G11
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... White hanes with 8 and ...
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B 9 H10
W 10 D11
B 11 C11
W 12 C10
B 13 G10
W 14 E6
B 15 D5
W 16 F4
B 17 F3
W 18 H4
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... manages to extricate her stones with the sequence to 18.
In the process, however, Black has secured the lower left corner
and his stones above are no longer in danger.
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B 19 M17
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Black now takes the big points of 19 ...
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W 20 K17
B 21 Q11
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... and 21, and he has a good game.
<=
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