(;AB[rr]AB[rs]AB[pr]AB[qq]AB[pp]AB[op]AB[oq]AB[qp]AB[or]AW[rq]AW[rp]AW[sr]AW[qo]AW[po]AW[oo]AW[no]AW[np]AW[nq]AW[nr]AW[ns]AW[qr]C[White to kill]AP[goproblems]
(;W[ps]LB[os:A]C[Good, black cannot play at A];B[qs];W[os]C[RIGHT])
(;W[qs];B[ps])
(;W[os];B[ps]))