(;SZ[19]AW[bn]AW[cn]AW[co]AW[do]AW[eo]AW[fo]AW[go]AW[bp]AW[gp]AW[bq]AW[dq]AW[eq]AW[gq]AW[br]AW[gr]AW[es]AW[gs]AB[ao]AB[bo]AB[ap]AB[cp]AB[dp]AB[ep]AB[fp]AB[cq]AB[fq]AB[cr]AB[fr]AB[fs]C[Best result for white?]GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2]RU[Japanese]KM[0.00]PW[White]PB[Black]PL[W] (;W[cs];B[bs] (;W[dr];B[ds]C[Black takes first in this ko.]) (;W[ds];B[ar]C[White has too much to lose in this ko.]) (;W[as];B[dr] (;W[ds];B[er]C[Black lives.]) (;W[bs];B[er]C[Black lives.])) (;W[an];B[ds]C[Black lives.])) (;W[dr];B[bs] (;W[an];B[ds];W[cs]C[ This is the best ko for both.RIGHT]) (;W[er];B[ds] (;W[er];B[ar]) (;W[an];B[er]C[Black lives.])) (;W[ar];B[cs] (;W[an];B[er]C[Black lives.]) (;W[er];B[ds] (;W[er];B[as]) (;W[an];B[er]C[Black lives.])))) (;W[bs];B[ds]C[Black lives.]) (;W[ds];B[cs];W[bs]C[Gote seki, white can do better.]) (;W[er];B[ds]C[Black lives.]) (;W[an];B[ds]C[Black lives.]))