(;AW[sp]AW[sq]AW[sr]AW[rs]AW[qs]AW[ns]AW[nr]AW[nq]AB[mr]AB[mq]AB[np]AB[oq]AB[or]AB[os]AB[pp]AB[qo]AB[ro]AB[so]AW[qq]TR[qq]TR[sp]TR[sq]TR[sr]TR[rs]TR[qs]C[Do your best.]AP[goproblems]
(;B[qr]
(;W[pr]
(;B[pq]
(;W[rp]
(;B[ps]
(;W[rr]
(;B[qp]C[Well done, ko is the best result for black.RIGHT])
(;B[pr];W[qp]))
(;W[qp];B[rr]))
(;B[qp];W[rr];B[ps];W[qr])
(;B[rr];W[rq]
(;B[qr];W[ps])
(;B[ps];W[qr])))
(;W[ps];B[rq]
(;W[rr];B[rp]C[RIGHT])
(;W[rp];B[qp]C[RIGHT])))
(;B[ps];W[pq]
(;B[ms];W[rq])
(;B[op];W[rq])
(;B[rq];W[op]))
(;B[rq];W[rp]
(;B[pq];W[rr])
(;B[ps];W[rr])
(;B[qp];W[rr]))
(;B[rp];W[rq])
(;B[rr];W[rq]))
(;W[rr];B[pr]
(;W[rp];B[qp]C[RIGHT])
(;W[qp];B[rp]C[RIGHT])))
(;B[rq];W[rp]
(;B[qp];W[qr])
(;B[qr];W[pr]
(;B[pq];W[rr])
(;B[ps];W[rr])
(;B[qp];W[rr]))
(;B[pr];W[qr]))
(;B[pr];W[qr])
(;B[rp];W[rq])
(;B[rr]C[Now, white is alive unconditionary.]))