(;GM[1]FF[4]SZ[19]
GN[If White tries to bridge under]
PC[http://senseis.xmp.net/?XuanxuanQijingProblem10/Attempts]AP[GoWiki:2009]
DT[2013-04-01]
C[Diagram from http://senseis.xmp.net/?XuanxuanQijingProblem10/Attempts

If White tries to bridge under]
PL[B]

AB[la][lb][qb][lc][mc][rc][sc][ld][pd][qd][rd][le][pe][lf][of][pf][mg][ng]
AW[ma][mb][ob][rb][sb][nc][pc][qc][md][od][me][oe][nf]

;B[pb]C[B1]MN[1]
;W[pa]C[W2]MN[2]
;B[oc]C[B3]MN[3]
;W[qa]C[W4]MN[4]

;
)
