(;AP[goproblems]AB[cb]AB[cc]AB[dc]AB[da]AB[ea]AB[eb]AW[bd]AW[cd]AW[dd]AW[ec]AW[fb]AW[fc]AW[fa]AW[ee]C[White to play.](;W[bb];B[bc](;W[ac];B[ab](;W[aa];B[ba];W[ca]C[White takes the ko first.RIGHT])(;W[ba];B[ad])(;W[ad];B[ba]))(;W[ba];B[ab])(;W[ab];B[ac])(;W[ca];B[ba]))(;W[ab];B[bb](;W[ba];B[ac];W[bc];B[aa]C[Black takes the ko first.])(;W[bc];B[ba])(;W[ac];B[ba]))(;W[bc];B[bb];W[ab];B[ba])(;W[ba];B[bb];W[ab];B[ac];W[bc];B[aa]C[Black takes the ko first.])(;W[ac];B[bb];W[ab];B[ba])(;W[ca];B[ba]))