(;
GM[1]
SZ[19]
AW[dd][dp][dn][qc][rd][ob][qf][pf][pg][ph][ng][qi][qj][oj]
AB[fp][mq][pp][ql][kc][pd][nd][qe][re][rf][qg][qh][oi][pi]
C[Problem 68. Black to play.  

How should Black attack the white stones on the right ? ]
(;B[nj]
TE[2]
C[Correct Answer.  

Black 1 ... ]
;W[pj]
C[... forces White to connect at 2. ]
;B[mi]
LB[ol:A][lg:B]
C[Black then plays 3 and the points A and B are miai. Whichever way White plays, she will lose some stones. <= ]
)
(;B[ni]
C[Correct Answer.  

Extending to Black 1 is the standard way to attack. ]
;W[pj]
C[After White defends with 2, ... ]
;B[ol]
C[... Black jumps to 3. Again, White is split into two groups; if she tries to save the one on the right side, her group above will die. <= ]
)
(;B[mi]
C[Failure.  

Black 1 is bad. ]
;W[pl]
C[White can now exchange 2 ... ]
;B[qm]
C[... for 3, ... ]
;W[ni]
C[... then wedge in at 4. ]
(;B[nj]
C[If Black ataris with 5, ... ]
;W[nh]
C[... White extends to 6, and, ... ]
;B[pj];W[ok]
C[... after White 8, the three black stones are trapped. <= ]
)
(;B[nh]
C[Black might atari from above with 5. ]
;W[nj];B[oh]
C[After Black connects at 7, ... ]
;W[oe]
C[... White peeps at 8, ... ]
;B[od];W[mh]
C[... then blocks with 10 and ... ]
;B[mg];W[lh];B[og];W[nf]
C[... the black stones are trapped. <= ]
))
)