(;AB[pb]AB[qb]AB[qc]AB[rd]AB[sd]AW[se]AW[re]AW[qe]AW[pc]AW[pd]AW[ob]AW[nc]AW[qd]TR[qd]C[Easy problem, black to avoid slipping up and losing the corner]AP[goproblems]
(;B[rc];W[sb]
(;B[ra];W[pa])
(;B[pa];W[ra])
(;B[rb];W[ra]))
(;B[sb];W[pa]
(;B[ra]C[R19 is betterRIGHT])
(;B[qa]C[White just has ko threats, well done :)RIGHT])
(;B[rc]C[RIGHT])
(;B[rb]C[RIGHT]))
(;B[rb];W[sb]
(;B[rc];W[ra])
(;B[ra];W[rc])
(;B[pa];W[rc])
(;B[sc];W[rc]))
(;B[ra];W[sb]
(;B[rc];W[pa])
(;B[pa];W[rc]))
(;B[pa];W[rc])
(;B[sc];W[sb]))