(;GM[1]FF[4]SZ[19]
GN[b above]
PC[https://senseis.xmp.net/?GokyoShumyoSection3Problem7/Solution]AP[GoWiki:2009]
DT[2023-01-01]
C[Diagram from https://senseis.xmp.net/?GokyoShumyoSection3Problem7/Solution

b above]
PL[W]

AB[ea][eb][bc][cc][dc]
AW[fb][ec][gc][bd][cd][dd][ed]

;W[ca]C[W1]MN[1]
;B[ba]C[B2]MN[2]
;W[bb]C[W3]MN[3]
;B[ab]C[B4]MN[4]

;
)
