(;AB[ad]AB[bd]AB[cd]AB[dd]AB[ee]AB[fe]AB[eg]AB[cg]AB[cf]AB[ch]AB[bg]AW[bb]AW[cc]AW[ec]AW[ed]AW[df]AW[de]AW[ce]AW[be]AW[bf]AW[af]C[The black and white groups touching the left edge have four liberties apiece. Since they are even, the side that plays first will win.]AP[goproblems]
(;B[ef];W[dc]
(;B[dg];W[bc];B[ag];W[ac];B[ae]C[If Black plays first, he ends by capturing White. Notice that he fills White's outside liberties first, saving the inside one for last.RIGHT])
(;B[ag];W[bc];B[dg];W[ac];B[ae]C[If Black plays first, he ends by capturing White. Notice that he fills White's outside liberties first, saving the inside one for last.RIGHT]))
(;B[ag];W[ac]
(;B[dg];W[bc];B[ef];W[dc];B[ae]C[If Black plays first, he ends by capturing White. Notice that he fills White's outside liberties first, saving the inside one for last.RIGHT])
(;B[ef];W[bc];B[dg];W[dc];B[ae]C[If Black plays first, he ends by capturing White. Notice that he fills White's outside liberties first, saving the inside one for last.RIGHT]))
(;B[dg];W[dc]
(;B[ef];W[bc];B[ag];W[ac];B[ae]C[If Black plays first, he ends by capturing White. Notice that he fills White's outside liberties first, saving the inside one for last.RIGHT])
(;B[ag];W[bc];B[ef];W[ac];B[ae]C[If Black plays first, he ends by capturing White. Notice that he fills White's outside liberties first, saving the inside one for last.RIGHT]))
(;B[ae];W[dc]C[If Black started from the inside, both groups would lose one liberty and suddenly White would be ahead. To fill from the outside is the first principle in fights like this.CHOICE]))