(;
AB[pa][oa][na][ma][la][ka][ja][qb][mb][lb][kb][jb][gb][rc][qc][nc][kc][ic][hc][nd][md][me][le][je][of][nf][pe][qf]
AW[sa][qa][ia][rb][pb][ob][nb][ib][oc][mc][jc][od][kd][oe][ne][mf][lf][kf]
C[Black plays.

Source:
    Igo Hatsuyo-ron #72:  300 year old
    problem set for student professionals.

Analysis:
    Myron Souris]
(;
B[lc]
C[Correct, although one line does require that a ladder be good for Black.];
W[ld]
C[Forced];
B[ke]
C[The only try if Black wants to kill everything.];
W[mc]C[Everything up to here is a one-way street.]
(;
B[lc]
C[The killing move.]
(;
W[mb];B[kc]
(;
W[kb];B[jd];W[lb];B[jb];W[ja];B[jc]
)
    (;
    W[jd]
    C[The ladder must work for Black.];
    B[jb];W[id];B[ie]
    )
)
    (;
    W[kc]
    C[White might hope for a ko, but ...];
    B[mb];W[lb];B[mc]
    C[Black simply connects to kill White.];
    W[ma]
    C[And if White plays here, White dies in gote!];
    B[]
    C[For example, when Black passes...];
    W[ka];B[jb];W[pa];B[na]
    C[White only has 1 eye.]
    )
)
    (;
    B[mb]
    C[Looks strong, but fails.];
    W[lc];B[lb];W[kb];B[jd];W[kc];B[ka];W[jb]
    C[White lives.]
    )
)
    (;
    B[ke]
    C[Fails];
    W[lc]
    C[White's eye space is smaller than in the correct line, but White's shape is much better.];
    B[kb]
    C[Black's only hope.];
    W[kc];B[lb];W[mb];B[ma];W[pa]
    C[And Black runs out of steam.]
    )
    (;
    B[jd]
    C[Fails];
    W[ke];B[lc];W[ld]
    C[And Black has a shortage of liberties.]
    )
)

