EVENT
BOARDSIZE 19
SETUP W D17 D3 C6 Q18 R18 R17 R16 R14 R13 O17 O15 O13 
SETUP B E18 F16 D15 B15 Q4 P12 Q13 Q14 Q17 Q16 Q15 P18 P17 
MARK A@P12
COM
Problem 124. White to play.  

Black has just played the diagonal move of A. What should White
do ? 
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W 1 R12
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

White 1 may be a hard move to see, but it is the key point in
this position.
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B 2 O12
COM
Black will push out with 2 ...
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W 3 N12
B 4 N11
COM
... and 4, ...
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W 5 M12
B 6 O10
COM
... but he must fall back and make shape with 6.
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W 7 M11
B 8 M10
W 9 L10
B 10 M9
W 11 L9
B 12 M8
W 13 L8
B 14 M7
W 15 K6
MARK 1@R12
COM
White now bears down on Black with the sequence to 15, building
influence in the center. This influence combines well with her
enclosure in the lower left corner, while Black's influence facing
the right is neutralised by the white stone at 1.
<=
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