(;
C[Black to play.
]
AW[ln][mn][nn][on][io][jo][ko][po][ip][mp][qp][rp][sp][gq][iq][kq][lq][mq][pq][jr][mr][or]
AB[lo][mo][no][jp][kp][lp][np][jq][nq][rq][sq][nr][qr][rs]
(;B[ns]
(;W[os];B[kr];W[lr]
(;B[ls];W[ks];B[ms];W[kr];B[ir]C[CHOICE RIGHT
])
(;B[ms];W[ks]
(;B[ls];W[kr];B[ir]C[CHOICE RIGHT
])
(;B[ir];W[ls];B[hr];W[gr]
(;B[js];W[is];B[hs];W[hq]C[Only ko.
])
(;B[hs];W[hq];B[js];W[is]C[Only ko.
])
)
)
(;B[ks];W[js]
(;B[ir];W[ls];B[hr];W[gr])
(;B[ms];W[ls])
)
(;B[ir];W[ks]
(;B[ms];W[ls];B[hr];W[gr]
(;B[js];W[is];B[hs];W[hq]C[Only ko.
])
(;B[hs];W[hq];B[js];W[is]C[Only ko.
])
)
(;B[is];W[hr])
)
)
(;W[kr]
(;B[pr];W[oq];B[os];W[ps];B[sr]C[CHOICE RIGHT
])
(;B[os];W[pr];B[ps];W[sr]C[Black dies.
])
)
)
(;B[kr];W[ns]LB[jr:A]
C[Even if black captures the stone at A he is dead.
])
(;B[os];W[pr]
(;B[ps];W[sr])
(;B[ns];W[kr];B[ps];W[sr])
)
(;B[ir];W[kr]C[Black achieves nothing.
])
(;B[ls];W[kr]
(;B[pr];W[oq];B[os];W[ps];B[ns];W[sr])
(;B[os];W[pr];B[ps];W[sr])
)
(;B[ms];W[kr]
(;B[os];W[pr];B[ps];W[sr])
(;B[pr];W[oq];B[os];W[ps]
(;B[sr];W[ns]C[Only ko.
])
(;B[ns];W[sr])
)
)
(;B[pr];W[ns]
(;B[oq];W[os]
(;B[ms];W[ls];B[ps];W[ms]C[2 against 3 liberties.
])
(;B[ps];W[ms])
)
(;B[kr];W[oq])
(;B[ls];W[ms];B[oq];W[os]C[It's 2 against 3 liberties.
])
)
)