(;
GM[1]
SZ[19]
AW[jc][pc][pe][rf]
AB[dc][cf][hc][qg][qj]
C[Problem 126. Black to play.  

This time the white enclosure is facing the other direction. Where should Black invade ? ]
;B[lc]
TE[2]
C[Correct Answer.  

Invading at 1 is the vital point. ]
(;W[kd]
C[White 2 is the standard response. ]
(;B[oc]
C[Next, Black attaches at 3, and, ... ]
;W[od];B[nc]
C[... after 5, ... ]
;W[pb];B[me]
C[... jumps to 7. <= ]
)
(;B[me]
LB[oc:@]
C[Variation.  

Instead of @, playing directly at 3 is also possible. <= ]
))
(;W[nc]
C[Variation.  

If White defends from the other side with 2, ... ]
;B[kd]
C[... Black attacks the lone white stone with 3. <= ]
)
)