(;AB[ra]AB[rb]AB[qb]AB[sd]AB[rd]AB[qd]AB[pd]AB[pc]AB[od]AB[nd]AB[mc]AB[lc]AB[kd]AB[jd]AB[jc]AB[kb]AB[ib]AB[ia]AB[ha]AW[ga]AW[gb]AW[hb]AW[ic]AW[ie]AW[ke]AW[ld]AW[md]AW[ne]AW[mf]AW[nc]AW[oc]AW[ob]AW[pb]AW[qa]AW[mb]AW[rc]C[Black to kill the invading white group.]AW[id]AW[je]AW[oe]AW[pe]AW[qe]AB[re]AW[rf]AW[qg]AP[goproblems]
(;B[lb]TR[na]TR[pa]C[Both black groups are alive and O19 and Q19 are miai.RIGHT])
(;B[na];W[lb]
(;B[kc];W[ka])
(;B[nb];W[kc])))