(;GM[1]FF[4]SZ[19]
GN[Five ko threats are left over.]
PC[http://senseis.xmp.net/?BeginnerExercise259/Attempts]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?BeginnerExercise259/Attempts

Five ko threats are left over.]
PL[B]

AB[ck][dk][hl][cm][dm][gm][lm][cn][hn][do][io][ko][lo][mo][cp][dp][gp][hp][ip][mp][dq][fq][gq][mq][cr][dr][er][fr][ds]
AW[hk][ik][gl][jl][fm][jm][bn][dn][en][gn][in][jn][bo][co][eo][jo][bp][ep][jp][kp][lp][bq][cq][eq][hq][iq][br][gr][hr][bs][cs]

;B[hm]C[B1]MN[1]
;W[fk]C[W2]MN[2]
;B[go]C[B3]MN[3]
;W[fn]C[W4]MN[4]
;B[fl]C[B5]MN[5]
;W[el]C[W6]MN[6]
;B[gk]C[B7]MN[7]
;W[gj]C[W8]MN[8]
;B[jq]C[B9]MN[9]

;
)
