(;GM[1]FF[4]SZ[19]
GN[Main line]
PC[http://senseis.xmp.net/?GokyoShumyoSection1Problem20/Solution]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?GokyoShumyoSection1Problem20/Solution

Main line]
PL[B]

AB[bq][cq][dq][eq][er]
AW[co][bp][dp][ep][fq][hq][br][fr]
LB[as:a]

;B[ar]C[B1]MN[1]
;W[cr]C[W2]MN[2]
;B[cs]C[B3]MN[3]
;W[ds]C[W4]MN[4]
;B[bs]C[B5]MN[5]

;LB[as:a]
)
