(;AB[ar]AW[bq]AW[ap]AW[cp]AW[dp]AW[dq]AW[dr]AW[cr]AW[ds]AB[bp]AB[bo]AB[co]AB[do]AB[eo]AB[ep]AB[eq]AB[er]AB[es]AW[bs]C[Black can't kill White but has the best result. CHOICEFORCE]AP[goproblems]
(;B[an]C[CHOICEFORCE];W[aq]C[CHOICEFORCE];B[ao]C[CHOICE])
(;B[ao]C[CHOICEFORCE];W[aq]C[CHOICE])
(;B[aq]C[CHOICEFORCE];W[br]C[CHOICEFORCE]
(;B[an]C[CHOICEFORCE];W[as]C[CHOICE])
(;B[ao]C[CHOICEFORCE];W[as]C[CHOICEFORCE];B[ap]C[CHOICERIGHT])))