(;AB[rr]AB[qr]AB[pq]AB[pp]AB[qp]AB[qo]AB[pn]AB[oo]AB[nq]AB[nr]AW[or]AW[pr]AW[qq]AW[rq]AW[rp]AW[ro]AW[qn]AW[qm]C[White to capture the corner.]AP[goproblems]
(;W[ps]
(;B[oq]C[CHOICE]
(;W[rs];B[sr]
(;W[sq]C[CorrectRIGHT])
(;W[qs]C[CorrectRIGHT]))
(;W[sr];B[sq]
(;W[sp];B[rs]
(;W[rn];B[ns];W[sq];B[os]C[Black win the capturing race :(])
(;W[sq];B[rn];W[rm];B[ns];W[sn];B[os]C[Black win the capturing race :(]))
(;W[rs];B[ss]C[Ko])
(;W[qs];B[ss]
(;W[sp];B[rn];W[sr]C[White risks too much in this ko.])
(;W[rn];B[ns];W[sp];B[os]C[Black win the capturing race :(]))))
(;B[rs];W[sr];B[sq];W[qs]))
(;W[sr];B[sq]
(;W[sp];B[rs]
(;W[ps];B[oq]
(;W[rn];B[ns];W[sq];B[os]C[Black win the capturing race :(])
(;W[sq];B[rn];W[rm];B[ns];W[sn];B[os]C[Black win the capturing race :(]))
(;W[qs];B[ps];W[os];B[oq];W[qs]C[Ko.])
(;W[sq];B[rn]
(;W[rm];B[os]C[Black win the capturing race.])
(;W[qs];B[ps];W[os];B[oq];W[qs]C[Ko])))
(;W[rs];B[ss]C[Ko])
(;W[qs];B[ss]
(;W[ps];B[oq]
(;W[sp];B[rn];W[sr]C[White risks too much in this ko.])
(;W[rn];B[ns];W[sp];B[os]C[Black win the capturing race :(]))
(;W[sp];B[rn];W[sr]C[White risks too much in this ko.])))
(;W[rs];B[qs]
(;W[sr];B[ss]C[Ko])
(;W[sq];B[oq];W[sr];B[ss]))
(;W[qs];B[rs];W[sr];B[ps];W[os];B[oq];W[qs]C[Ko]))