(;AB[cr]AB[cq]AB[bq]AB[ap]AB[bo]AB[ds]AB[er]AB[fq]AB[gr]AB[gp]AB[fo]AB[fn]AB[en]AB[dm]AB[bl]AB[ck]AW[br]AW[bp]AW[cp]AW[bn]AW[cn]AW[do]AW[eo]AW[ep]AW[eq]AW[dq]AW[dr]AP[goproblems]
(;W[as];B[cs];W[aq];B[ar]C[Ko! The only solution.RIGHT])
(;W[co];B[ao]
(;W[as];B[cs];W[aq];B[ar]C[Starting at A1 with white is better, because of the extra ko threat on C5.])
(;W[an];B[aq];W[ar];B[cs]C[Dead!])
(;W[ar];B[aq];W[an];B[cs]C[Dead!]))
(;W[an];B[ao]
(;W[as];B[cs];W[aq];B[ar]C[Starting at A1 with white is better, because of the extra ko threat on C5.])
(;W[ar];B[aq];W[co];B[cs]C[Dead!])))