(;
GM[1]
SZ[19]
AW[dd][dq]
AB[pp][qd][oc]
LB[qd:1][oc:5][pp:3][dq:4][dd:2]
C[Problem 52. White to play.  

What should White do after Black makes a corner enclosure with 5 ? ]
(;W[qj]
TE[2]
C[Correct Answer.  

White should break up Black's formation on the right side by playing at 1. <= ]
)
(;W[co]
C[Failure.  

Making a corner enclosure in the lower left corner with 1 is passive. ]
;B[qj]
C[Black will take this opportunity to build a strong formation on the right side with 2, which is an ideal extension from both the corner enclosure at the top and the star point at the bottom. <= ]
)
)