(;
GM[1]
SZ[19]
AW[ch][jc][je][lc][pc][qc][qb][rd][re][qe][qf]
AB[dc][cf][hc][nc][pb][rc][pe][pd][qd][ne]
LB[re:2][rc:1]
C[Problem 106. Black to play.  

White answers the cut of Black 1 with 2. What should Black do now ? ]
(;B[rb]
TE[2]
C[Correct Answer.  

Black should play 1. ]
(;W[ob]
C[White has no choice but to atari with 2. ]
;B[oc]
C[Now Black can make good shape by playing atari with 3. <= ]
)
(;W[oc]
C[If White plays 2 here, ... ]
;B[ob]
C[... Black plays 3 and the white stones will be captured. <= ]
))
(;B[oc]
C[Failure.  

Black 1 also makes shape, ... ]
;W[rb]
C[... but after White 2, there is no play left for Black in the corner. See the next problem for amplification. <= ]
)
)