(;AW[sc]AW[rd]AW[qc]AW[pc]AW[oc]AW[ob]AW[oa]AB[na]AB[nb]AB[nc]AB[nd]AB[od]AB[pd]AB[qd]AB[re]AB[se]AB[sa]AB[pa]C[Black to kill]AP[goproblems]
(;B[rb]
(;W[qb];B[rc];W[ra]
(;B[sd];W[sb]
(;B[sa]C[RIGHT])
(;B[rd]C[RIGHT]))
(;B[qa]C[RIGHT]))
(;W[rc]
(;B[qb]
(;W[sb];B[ra]LB[pb:A]C[White can't give atariRIGHT])
(;W[pb];B[qa]LB[sb:A]C[White can't give atariRIGHT]))
(;B[qa];W[sb]
(;B[qb];W[ra]C[Only ko])
(;B[ra];W[qb]C[White is alive]))
(;B[ra];W[qb];B[qa];W[sb]C[White is alive])))
(;B[qb];W[rb];B[ra];W[sd]C[White is alive in a seki])
(;B[ra];W[qb];B[qa];W[rb]C[White is alive])
(;B[sd];W[rc];B[rb]
(;W[qa];B[qb];W[pb]C[White is alive in a seki])
(;W[qb];B[qa]C[White is alive in a seki])
(;W[sb]
(;B[ra];W[qb]C[White is alive])
(;B[qa];W[ra]C[Only ko]))))