(;AB[bb]AB[cb]AB[eb]AB[ec]AB[ed]AW[bc]AW[cc]AW[fb]AW[fc]AW[fd]AW[fe]AB[bd]AW[be]AW[ce]AW[de]C[Black to live.]AP[goproblems]
(;B[cd]
(;W[ad]
(;B[ab]
(;W[dc]
(;B[dd];W[ac];B[db];W[ae]
(;B[ea]C[Good job!RIGHT])
(;B[ba]C[RIGHT]))
(;B[db];W[dd];B[ea]C[RIGHT]))
(;W[dd];B[ea]C[RIGHT]))
(;B[dc];W[ab];B[ac];W[bc])
(;B[dd];W[ab]))
(;W[dd];B[dc];W[ad]
(;B[ab];W[ea];B[da];W[fa];B[ba];W[ee];B[db]C[RIGHT])
(;B[da];W[fa]
(;B[ea];W[ab];B[ba]C[RIGHT])
(;B[ab];W[ea];B[ba]C[RIGHT];W[ee];B[db]C[RIGHT]))))
(;B[ab];W[dc];B[db];W[ea]C[Dead.])
(;B[dc];W[ab]C[Dead.]
(;B[cd];W[ad]
(;B[ac];W[bc])
(;B[ba];W[da]
(;B[ac];W[bc])
(;B[dd];W[ac])
(;B[aa];W[dd]))
(;B[da];W[ba]))
(;B[ba];W[da]
(;B[cd];W[ad]
(;B[ac];W[bc])
(;B[dd];W[ac])
(;B[aa];W[dd]))
(;B[ac];W[cd])))
(;B[ac]C[From Sakata Eio's book How to Defend Weak Groups. Black to live.];W[dc];B[db];W[ea]C[Dead.]))