My first problem on goproblems.com, please tell me if something is wrong or if I have to add variation :)
(;AP[goproblems]AW[ac]AW[bc]AW[cb]AW[db]AW[cd]AB[bd]AB[ad]AB[be]AB[ce]AB[dc]AB[dd]AB[eb]AB[fc]C[White to live.](;W[ba](;B[da];W[ab]C[RIGHT])(;B[ab];W[da](;B[cc];W[bb]C[RIGHT])(;B[bb](;W[cc];B[ea];W[aa]C[RIGHT])(;W[aa]C[RIGHT]))))(;W[da];B[ba]C[White has only one eye.CHOICE](;W[bb];B[aa])(;W[ca];B[bb](;W[ab];B[cc])(;W[cc];B[ea]))(;W[aa];B[ab](;W[bb];B[aa])(;W[ca];B[cc];W[bb];B[ea])))(;W[ab];B[ba]C[White has only one eye.CHOICE];W[da];B[ea])(;W[cc](;B[ba]C[White has only one eye.CHOICE])(;B[da](;W[ba];B[ab]C[CHOICE])(;W[ca];B[ea](;W[aa];B[bb]C[CHOICE])(;W[ba];B[ab]C[CHOICE])(;W[ab];B[ba]C[CHOICE])(;W[bb];B[aa]C[CHOICE]))))(;W[bb];B[da](;W[ca];B[aa]C[CHOICE])(;W[aa];B[ca]C[CHOICE];W[ba];B[ea])(;W[ea];B[fa](;W[ca];B[aa]C[CHOICE])(;W[aa];B[ca]C[CHOICE];W[ba];B[ea])))(;W[aa];B[da](;W[ca];B[bb]C[CHOICE])(;W[ba]C[CHOICE])(;W[bb];B[ca]C[CHOICE];W[ba];B[ea]))(;W[ca]C[White can't make two eye in the corner.CHOICE];B[ba];W[bb];B[aa])(;W[ea];B[ba]))