(;AW[dr]AW[dq]AW[dp]AW[co]AW[bo]AW[cm]AB[cp]AB[do]AB[eo]AB[em]AB[ep]AB[eq]AB[er]C[play the best endgame for black]AP[goproblems]
(;B[cr];W[cq];B[bq];W[ds]C[should the ko be bad for white, white should play at b4 which would lead to the same result as the solution])
(;B[ds];W[bq])
(;B[bq];W[cq];B[ds];W[cr];B[br];W[bp];B[cs];W[cp];B[aq]C[RIGHT]))