(;AP[goproblems]AW[br][ep]AW[cr]AW[aq]AW[ap]AW[bo]AW[co]AW[do]AW[eo]AW[dq]AW[eq]AW[er]AW[fq]AB[bp]AB[cp]AB[ao]AB[an]AB[bn]AB[cn]AB[dn]AB[dl]AB[fm]AB[gn]AB[fp]AB[gp]AB[gq]AB[hr]AB[fr]AB[fs]AB[es]AB[ds]AB[dr]C[Black to kill.](;B[ar](;W[as](;B[bq];W[ar](;B[cs]LB[as:D]LB[ar:D]LB[aq:D]LB[ap:D]LB[bo:D]LB[co:D]LB[do:D]LB[eo:D]LB[fq:D]LB[er:D]LB[dq:D]LB[eq:D]LB[cr:D]LB[br:D]C[Correct. The white stones is dead. (marked D)RIGHT])(;B[cq];W[dp];B[cs]C[RIGHT])(;B[ep];W[dp];B[cs];W[cq];B[bp]C[RIGHT]))(;B[cs];W[bs];B[bq]C[RIGHT]))(;W[bq];B[bs]C[RIGHT]))(;B[bq];W[ar])(;B[bs];W[cs];B[bq];W[ar])(;B[cs];W[bs](;B[ar];W[bq])(;B[bq];W[ar])))