(;
GM[1]
SZ[19]
AW[bd][cf][ci][ic][lc][qf][qi]
AB[cc][dd][fc][nc][pd][rd]
C[Problem 149. White to play.  

Here is another tight black formation. Can White invade Black's corner and live ? ]
(;W[qc]
TE[2]
C[Correct Answer.  

The moves from White 1 ... ]
;B[qd];W[ob];B[nb];W[oc];B[od];W[rc]
C[... to 7 are all good, but Black is too strong here and ... ]
;B[pc];W[pb];B[rb]
C[... White has no answer to Black 10. <= ]
)
(;W[re]
C[Alternative.  

Since White is unable to invade Black's corner, she should make this area as small as possible ... ]
;B[qc];W[nb];B[ob];W[nd]
LB[re:1][nb:3]
C[... by playing the forcing moves of 1, 3, and 5. <= ]
;B[oc])
)