(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
PB[Black to play]C[Just play through the moves to move 32 which is the problem position. These do not represent a game sequence!]
;B[sq]
;W[sp]
;B[sr]
;W[rp]
;B[rr]
;W[rq]
;B[qq]
;W[qp]
;B[pq]
;W[pp]
;B[op]
;W[po]
;B[nq]
;W[ro]
;B[qo]
;W[pn]
;B[qn]
;W[qm]
;B[rn]
;W[rm]
;B[sn]
;W[]
;B[on]
;W[]
;B[om]
;W[]
;B[pl]
;W[]
;B[qk]
;W[]
;B[rk]
;W[]C[This is the problem position. Black to play.]
(;B[pm]
;W[sm]
;B[oo]
;W[so]C[Filling either outside liberty lets white
capture with an L-four living shape.])
(;B[sl]
;W[sm]C[Again white captures to make L-four life.])
(;B[sm]C[Correct: Black must sacrifice one more stone!]
;W[sl]
;B[rl]
;W[so]
;B[sm]C[Then black throws back in and white cannot live]
(;W[sn]
;B[qn]C[Black stops white getting two eyes])
(;W[qn]
;B[sn]
;W[rn]
;B[sm]C[Throw-in again falses the edge eye - white dies.])))
