(;GM[1]FF[4]SZ[19]
GN[Hardest line]
PC[https://senseis.xmp.net/?KyuExercise140/Solution]AP[GoWiki:2009]
DT[2023-02-20]
C[Diagram from https://senseis.xmp.net/?KyuExercise140/Solution

Hardest line]
PL[B]

AB[rq][sq][nr][or][sr]
AW[po][op][qp][rp][sp][mq][nq][mr][ms]

;B[qr]C[B1]MN[1]
;W[rs]C[W2]MN[2]
;B[ns]C[B3]MN[3]
;W[pr]C[W4]MN[4]
;B[pq]C[B5]MN[5]
;W[ps]C[W6]MN[6]
;B[qs]C[B7]MN[7]
;W[oq]C[W8]MN[8]
;B[os]C[B9]MN[9]

;
)
