Easy life-and-death problem that came up in a game I played.
(;SZ[19]GM[1]FF[4]AP[glGo:1.3.1]ST[1]AB[ie]AB[jf]AB[je]AB[jd]AB[kf]AB[ke]AB[kd]AB[ma]AB[lb]AB[lc]AB[ld]AB[mc]AB[nd]AB[oe]AB[od]AB[pa]AB[pc]AB[pd]AB[qb]AB[qa]AW[pe]AW[pf]AW[qf]AW[rb]AW[ra]AW[mg]AW[lg]AW[kg]AW[jg]AW[if]AW[hf]AW[he]AW[hd]AW[id]AW[ib]AW[jc]AW[kc]AW[kb]AW[ka]AW[la]AW[me]AW[of]AW[ne]AW[qd]AW[qc]PW[White]PB[Black]C[White to kill. This position came up in the endgame (I was white, six-stone handicap). I had just cut off Black from a strong group on the left side.Any corrections / comments are welcome.](;W[ob];B[nb](;W[pb];B[oc](;W[oa]LB[md:B]LB[na:A]C[A and B are miai for the kill.RIGHT])(;W[md];B[oa])(;W[na];B[oa]))(;W[oa];B[pb]C[The almost fill does not work - Black has two eyes.])(;W[oc];B[pb]C[The almost fill does not work - Black has two eyes.])(;W[na];B[oa])(;W[nc];B[oc]))(;W[nb];B[ob](;W[mb];B[nc];W[na];B[oa]C[This is even worse than failing, as White must play at A to protect her three stones.])(;W[na];B[nc];W[mb];B[oa]LB[ma:A]C[This is even worse than failing, as White must play at A to protect her three stones.]))(;W[md](;B[ob];W[nb];B[mb];W[nc];B[oc])(;B[nb];W[ob];B[pb]))(;W[oa];B[ob](;W[nb];B[na])(;W[pb];B[nb])(;W[nc];B[nb])(;W[md];B[na]))(;W[nc];B[nb])(;W[na];B[ob]))
