(;
GM[1]
SZ[19]
AW[cc][dd][df][dp][qi][oi][pm][qn][po]
AB[db][fc][ic][pd][qg][qo][qp][pq][nq]
TR[oi]
C[Problem 73. Black to play.  

When White jumps into the center with the marked stone, the skirmish on the right side comes to a pause. Where should Black play next ? ]
;B[ck]
TE[2]
C[Correct Answer.  

Black should break up White's position on the left with 1. ]
(;W[ci]
C[If White next plays 2, ... ]
;B[cn]
C[... Black can extend to 3. ]
;W[co]
C[After the exchange of White 4 ... ]
;B[dn]
C[... for Black 5, ... ]
;W[fp]
LB[fq:A]
C[... White will play either 6 or A. <= ]
)
(;W[cm]
C[Variation.  

If White 2 here, ... ]
;B[ch]
LB[ck:1]
C[... Black will extend to 3. No matter how White attacks, Black can easily settle his stones on the left side, so Black 1 is the perfect point to play. <= ]
)
)