(;GM[1]FF[4]SZ[19]
GN[Weak defense at W4]
PC[https://senseis.xmp.net/?XuanxuanQijingProblem240/Solution]AP[GoWiki:2009]
DT[2023-02-04]
C[Diagram from https://senseis.xmp.net/?XuanxuanQijingProblem240/Solution

Weak defense at W4]
PL[B]

AB[cf][ch][dh][ej][el][em][cn][en][co][bp][cq]
AW[ci][cj][ck][cm][dm][bn][bo]

;B[bl]C[B1]MN[1]
;W[bm]C[W2]MN[2]
;B[bi]C[B3]MN[3]
;W[aj]C[W4]MN[4]
;B[ak]C[B5]MN[5]
;W[ao]C[W6]MN[6]
;B[am]C[B7]MN[7]

;
)
