(;
GM[1]
SZ[19]
AW[lc][md][pc][qe][cf][df][ci]
AB[ce][dd][fd][jc][nc]
LB[md:1]
TR[nc]
C[Problem 87. Black to play.  

What should Black do when White tries to enclosure the marked stone with the diagonal move of 1 ? ]
(;B[od]
TE[2]
C[Correct Answer.  

Black should answer with 1. ]
;W[ne]
C[If White continues with 2, ... ]
;B[pd];W[qd];B[qc]
LB[pd:3]
C[... Black pushes through and cuts with 3 and 5, ... ]
;W[pb];B[of]
LB[qc:5][oe:A]
C[... then jumps to 7. White cannot push through at A because of the aji of 5. <= ]
)
(;B[nd]
C[Failure.  

Black 1 is bad. ]
;W[ne]
(;B[oe];W[od]
LB[ne:2]
C[White confines the black stones to the top with 2 and 4. <= ]
)
(;B[pd]
C[If Black plays 3 here, ... ]
;W[qd];B[oe];W[pe];B[od];W[of]
C[... the moves to White 8 follow and Black's stones are almost dead. <= ]
))
)