EVENT
BOARDSIZE 19
SETUP W L17 M16 P16 Q17 R17 
SETUP B D17 C15 J17 N17 S17 R16 S15 Q14 
MARK 2@M16 1@N17
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Problem 40. Black to play.  

White responds Black's invasion with the diagonal move of 2.
How should Black respond ? 
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B 1 N16
USER
CORRECT ANSWER
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COM
Correct Answer.

Black should push up with 1, ...
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W 2 N15
B 3 L18
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... then attach with 3.
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W 4 K18
B 5 M18
W 6 K17
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After White 6, ...
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B 7 J18
W 8 O15
B 9 K19
MARK 7@J18
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... Black links up his stones with 7 and 9, ...
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W 10 K15
MARK 8@O15
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... while White makes thickness in the center with 8 and 10.
<=
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