(;GM[1]FF[4]SZ[19]
GN[Proof]
PC[https://senseis.xmp.net/?BeginnerExercise71/Solution]AP[GoWiki:2009]
DT[2024-09-04]
C[Diagram from https://senseis.xmp.net/?BeginnerExercise71/Solution

Proof]
PL[B]

AB[ba][ea][cb][eb][ec][bd][ed][be][ce][de][ee]
AW[da][ab][bb][db][bc][dc][ad][cd][dd]

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

;
)
