(;GM[1]FF[4]SZ[19]
GN[solution (4') (playing two ko threats at once ; 6 takes back (at corner), 9 at 1)]
PC[http://senseis.xmp.net/?XuanxuanQijingProblem35/Solution]AP[GoWiki:2009]
DT[2013-04-01]
C[Diagram from http://senseis.xmp.net/?XuanxuanQijingProblem35/Solution

solution (4') (playing two ko threats at once ; 6 takes back (at corner), 9 at 1)]
PL[W]

AB[cq][dq][eq][fq][gq][br][dr][er][fr][gr][as][cs][fs][gs][hs][is][js]
AW[bo][cp][dp][ep][fp][gp][hp][aq][bq][hq][ar][hr][ir][jr][kr]

;W[bs]C[W1]MN[1]
;B[ks]C[B2]MN[2]
;W[lr]C[W3]MN[3]
;B[ls]C[B4]MN[4]
;W[mr]C[W5]MN[5]
;W[ds]C[W7]MN[7]
;B[es]C[B8]MN[8]
;W[bs]C[W9]MN[9]

;
)
