(;AB[ap]AB[an]AB[bo]AB[co]AB[do]AB[dp]AB[cm]AB[dm]AB[en]AB[fo]AB[gp]AB[gq]AB[gr]AB[eq]AW[bq]AW[bp]AW[cp]AW[dq]AW[cr]AW[ep]AW[eo]AW[dn]AW[cn]C[b to kill]AP[goproblems]
(;B[dr];W[er]C[ko is not a solution]
(;B[ar];W[br])
(;B[cq]C[NOTTHIS])
(;B[br];W[ar])
(;B[ds];W[fq])
(;B[es];W[ds]))
(;B[er];W[dr];B[ar];W[aq])
(;B[bs];W[er]
(;B[br];W[ar])
(;B[ar];W[aq];B[br];W[ao])
(;B[ds];W[cs]))
(;B[br];W[ar]
(;B[dr];W[bs])
(;B[bs];W[er]))
(;B[ds];W[dr]
(;B[ar];W[aq];B[br];W[ao]C[ko])
(;B[br];W[ar]))
(;B[cs];W[er]
(;B[ar];W[br])
(;B[br];W[ar]))
(;B[ar]
(;W[aq]C[CHOICE]
(;B[br];W[ao]C[ko])
(;B[dr];W[er]C[remember, - ko is not a solution!CHOICE]
(;B[br]C[double ko. w is dead, long live w!];W[ao]
(;B[cq]C[w is dead on double koRIGHT])
(;B[bn];W[ds])
(;B[fp];W[ds]))
(;B[cq]C[NOTTHIS])
(;B[fp];W[ds])
(;B[ds];W[fq])
(;B[fq];W[ds]))
(;B[er];W[dr];B[br];W[ao]))
(;W[er];B[br]C[RIGHT])
(;W[br];B[er]C[RIGHT]))
(;B[bn];W[er])
(;B[aq];W[ar];B[dr];W[er]))