White thank that he have corner... In my game he lost anything.
(;AW[br]AW[cq]AW[dr]AW[ds]AW[cp]AW[bo]AW[cn]AW[cm]AW[dm]AW[cl]AW[ck]AW[bk]AW[ak]AB[es]AB[er]AB[eq]AB[dq]AB[dp]AB[do]AB[co]AB[dn]AB[en]AB[em]AB[el]AB[dl]AB[dj]AB[dk]AB[cj]AB[bj]AB[aj]C[Reduce White as much as you can.
Only the best result counts.]AP[goproblems]
(;B[bp];W[bn]C[]
(;B[bq];W[cr]C[not right])
(;B[cr];W[bq]C[]
(;B[cs];W[bs]C[White happily plays B1, saving 3 points.])
(;B[bs];W[ar]C[Thanks to kaf for B1.
You reduced the corner to 9 points.
White will need an extra move to capture B4 later on.RIGHT])
(;B[ap];W[cs]))
(;B[cs];W[cr]C[])
(;B[bs];W[cr]))
(;B[bn];W[bm]C[]
(;B[bp];W[an]
(;B[bq];W[cr]C[])
(;B[cr];W[bq]C[]
(;B[cs];W[bs]C[White happily plays B1.
This is 3 points worse than the correct solution.])
(;B[bs];W[ar]C[Thanks to tails for B1.
You reduced the corner to 9 points.
White will need an extra move to capture B4 later on.RIGHT])
(;B[ap];W[cs]))
(;B[bs];W[cr]))
(;B[cr];W[bq]
(;B[bs];W[ar]C[You reduced the corner to 10 points; one point more than necessary.
Not playing at B4 earlier on (forcing White A6) was a mistake as now White no longer needs an extra move.])
(;B[cs];W[bs]C[White happily plays B1.
This is 3 points worse than the correct solution.]))
(;B[an];W[bp]))
(;B[cr];W[bq]C[]
(;B[bs];W[ar]C[You reduced the corner to 10 points; one point more than necessary.
Not playing at B4 earlier on (forcing White to defend around A6) was a mistake as now White no longer needs an extra move.])
(;B[cs];W[bs]C[White happily plays B1.
This is 3 points worse than the correct solution.])
(;B[bn];W[bm]
(;B[bs];W[ar]C[You reduced the corner to 10 points; one point more than necessary.
Not playing at B4 earlier on (forcing White A6) was a mistake as now White no longer needs an extra move.])
(;B[cs];W[bs]C[White happily plays B1.
This is 3 points worse than the correct solution.])))
(;B[bs];W[cr]))