(;GM[1]FF[4]SZ[19]
GN[Ko]
PC[https://senseis.xmp.net/?GokyoShumyoSection3Problem4/Solution]AP[GoWiki:2009]
DT[2023-01-01]
C[Diagram from https://senseis.xmp.net/?GokyoShumyoSection3Problem4/Solution

Ko]
PL[W]

AB[ec][fc][cd][dd][be][cf]
AW[cc][dc][bd]

;W[bb]C[W1]MN[1]
;B[ad]C[B2]MN[2]
;W[ac]C[W3]MN[3]

;
)
