(;GM[1]FF[4]SZ[19]
GN[Black to play]
PC[https://senseis.xmp.net/?XuanxuanQijingProblem321/Solution]AP[GoWiki:2009]
DT[2023-02-10]
C[Diagram from https://senseis.xmp.net/?XuanxuanQijingProblem321/Solution

Black to play]
PL[B]

AB[jc][oc][pc][qc][jd][od][je][ne][oe][kf][of][kg][lg][ng][mh][oh]
AW[mb][lc][nc][kd][nd][ke][me][lf][mf][nf][mg]

;B[md]C[B1]MN[1]
;W[ob]C[W2]MN[2]
;B[le]C[B3]MN[3]
;W[kb]C[W4]MN[4]

;
)
