(;GM[1]FF[4]SZ[19]
GN[Solution]
PC[https://senseis.xmp.net/?BeginnerExercise69/Solution]AP[GoWiki:2009]
DT[2024-09-04]
C[Diagram from https://senseis.xmp.net/?BeginnerExercise69/Solution

Solution]
PL[B]

AB[ao][bo][co][ap][cp][cq][cr][as]
AW[an][bn][cn][dn][do][bp][dp][dq][dr][cs]
LB[aq:a][bq:b][bs:c][ds:d]

;B[br]C[B1]MN[1]

;LB[aq:a][bq:b][bs:c][ds:d]
)
