(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2] RU[Japanese]SZ[9]KM[0.00] PW[White]PB[Black]AW[db][hb][ec][gc][hc][dd][ed][fd][gf][hf][if]AB[ha][bb][eb][fb][gb][cc][dc][fc][cd][ce][df][ef][fg][gg][hg][hh] (;B[id] (;W[ga]C[CHOICE] (;B[fa] ;W[ia] ;B[ib] ;W[hd] (;B[fe] ;W[da] ;B[cb] ;W[ge] ;B[ie] ;W[ic] ;B[ca] ;W[ia] ;B[ea] ;W[ga]C[RIGHT Best possible ko]) (;B[da] ;W[fe]) (;B[ge] ;W[fe]) (;B[ic] ;W[ie]) (;B[cb] ;W[fe])) (;B[da] ;W[ia] (;B[fe] ;W[ic] ;B[ge] ;W[he]) (;B[ic] ;W[fe] ;B[hd] ;W[gd] (;B[he] ;W[ie]) (;B[ib] ;W[ha])) (;B[hd] ;W[gd] (;B[fe] ;W[ic]) (;B[ic] ;W[fe] (;B[he] ;W[ie]) (;B[ib] ;W[ha])) (;B[ge] ;W[fe])) (;B[ge] ;W[fe])) (;B[fe] ;W[ea])) (;W[ea]C[CHOICE] (;B[ga] ;W[ib] (;B[cb] ;W[fe] (;B[hd] ;W[gd] (;B[he] ;W[ie] ;B[ff]C[RIGHT E9 was not the best possible move for white, you can see it in the solution.]) (;B[ff] ;W[he])) (;B[he] ;W[hd]) (;B[ff] ;W[hd])) (;B[da] ;W[ca]C[Ko from nothing])) (;B[fe] ;W[ga]) (;B[gd] ;W[ga]) (;B[hd] ;W[ga]) (;B[cb] ;W[ga] ;B[da] ;W[ia] (;B[fe] ;W[ic] (;B[ge] ;W[he]) (;B[hd] ;W[gd])) (;B[ic] ;W[fe] ;B[hd] ;W[gd] (;B[he] ;W[ie]) (;B[ib] ;W[ha])) (;B[hd] ;W[gd] (;B[ge] ;W[fe]) (;B[fe] ;W[ic]) (;B[ic] ;W[fe] (;B[he] ;W[ie]) (;B[ib] ;W[ha]))) (;B[ge] ;W[fe])))) (;B[ib] ;W[ga] (;B[fa] ;W[da] (;B[cb] ;W[ic] (;B[fe] ;W[ia]C[Not the best ko (2 step ko)]) (;B[ca] ;W[ia] (;B[fe] ;W[ga]C[Not the best ko (2 step ko)]) (;B[ea] ;W[fe])) (;B[hd] ;W[gd] (;B[he] ;W[ia]C[Not the best ko (2 step ko)]) (;B[fe] ;W[ia]C[Not the best ko (2 step ko)]))) (;B[ca] ;W[ic] (;B[cb] ;W[ia] (;B[ea] ;W[fe]) (;B[fe] ;W[ga]C[Not the best ko (2 step ko)])) (;B[fe] ;W[ia]C[Not the best ko (2 step ko)]) (;B[hd] ;W[gd] (;B[he] ;W[ia]C[Not the best ko (2 step ko)]) (;B[fe] ;W[ia]C[Not the best ko (2 step ko)]))) (;B[fe] ;W[ea]) (;B[gd] ;W[ea])) (;B[da] ;W[ic] (;B[fe] ;W[ia] ;B[ge] ;W[he]) (;B[fa] ;W[ia] (;B[fe] ;W[ga]C[Not the best ko (2 step ko)]) (;B[cb] ;W[fe]) (;B[hd] ;W[gd] (;B[he] ;W[ga]C[Not the best ko (2 step ko)]) (;B[fe] ;W[ga]C[Not the best ko (2 step ko)]))))) (;B[ga] ;W[fe] (;B[ib] ;W[hd]) (;B[hd] ;W[id] (;B[he] ;W[ib]) (;B[ib] ;W[he])) (;B[he] ;W[hd]) (;B[id] ;W[hd])) (;B[fe] ;W[ea] (;B[ga] ;W[ib] (;B[cb] ;W[id]) (;B[ge] ;W[ia]) (;B[id] ;W[ia])) (;B[cb] ;W[ga] ;B[da] ;W[ia] (;B[ge] ;W[he] (;B[id] ;W[ic]) (;B[fa] ;W[ha] ;B[id] ;W[ic])) (;B[id] ;W[ic] ;B[ge] ;W[he]) (;B[gd] ;W[ge])) (;B[ge] ;W[ga]) (;B[id] ;W[ga])) (;B[hd] ;W[id] (;B[he] ;W[ib]) (;B[ib] ;W[he]) (;B[gd] ;W[he])) (;B[ge] ;W[fe]) (;B[gd] ;W[ge] (;B[hd] ;W[id]) (;B[fe] ;W[ea] (;B[ga] ;W[ib] (;B[cb] ;W[hd]) (;B[hd] ;W[id])) (;B[cb] ;W[ga] ;B[da] ;W[ia])) (;B[ga] ;W[hd])) (;B[da] ;W[fe] (;B[hd] ;W[id]) (;B[ib] ;W[hd])))