(;SZ[19]AB[hs]AB[hr]AB[iq]AB[ip]AB[jp]AB[os]AB[or]AB[nq]AB[mp]AB[oq]AB[hq]AB[kp]AB[lp]AW[is]AW[ir]AW[jq]AW[kr]AW[kq]AW[ns]AW[nr]AW[mq]AW[lr]AW[hp]AW[ho]AW[no]AW[oo]C[Black to play and kill white.]HA[0]KM[5.5]
(;B[js];W[jr]
(;B[mr];W[ms]
(;B[lq];W[ks];B[mr]C[This is a ko and a failure for black if white got good enough ko-threats.])
(;B[ks];W[lq])
(;B[ls];W[ks];B[lq];W[mr]))
(;B[ks];W[ls]
(;B[lq];W[mr])
(;B[mr];W[ms];B[lq]C[RIGHT]))
(;B[ls];W[ks]
(;B[lq];W[mr])
(;B[mr];W[ms];B[lq];W[mr])
(;B[ms];W[mr]))
(;B[ms];W[mr]
(;B[ks];W[ls])
(;B[ls];W[ks])))
(;B[ls];W[ks]
(;B[ms];W[mr])
(;B[mr];W[ms];B[lq];W[mr])
(;B[lq];W[mr]))
(;B[ms];W[mr]
(;B[js];W[jr]
(;B[ks];W[ls])
(;B[ls];W[ks]))
(;B[jr];W[js])
(;B[ks];W[ls]
(;B[js];W[jr])
(;B[jr];W[js])))
(;B[ks];W[ls]
(;B[lq];W[js];B[mr];W[ms]C[White got two eyes.])
(;B[js];W[jr]
(;B[lq];W[mr]C[White got two eyes.])
(;B[mr];W[ms];B[lq]C[RIGHT])))
(;B[jr];W[js]
(;B[lq];W[mr]C[White got two eyes.])
(;B[ks];W[ls];B[lq];W[mr])
(;B[ls];W[mr])
(;B[mr];W[ms];B[lq];W[mr]C[White got two eyes.])
(;B[ms];W[mr]))
(;B[mr];W[ms]
(;B[lq];W[js]
(;B[mr];W[ls])
(;B[ls];W[mr]))
(;B[jr];W[js]
(;B[ls];W[ks];B[lq];W[mr])
(;B[ks];W[ls];B[lq];W[mr]C[White got two eyes.]))
(;B[ks];W[ls]
(;B[lq];W[js])
(;B[js];W[jr];B[lq]C[RIGHT]))))