Problem	1868
Created	2003-01-09
Name	the small board and the ko, supplement (2)
Source	ferdi
Rating

Difficulty	7 dan
Average Solve Time	80 secs
User Attempts	312 / 2677
Solve Ratio Rating	3 dan
	rating history

This the same position as in problem 1867. The marked white stone was a mistake - now black can win despite of the komi!

(;GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2] RU[Japanese]SZ[7]KM[0.50]TM[] AW[ec][ad][cd][ed][ae][ce][de][ee][fe][ge][bf][ag]AB[ea][eb][gb][bc][cc][dc][fc][bd][dd][fd][gd][be][cf]TR[ad]C[No prisoners, but a 3 point komi for white - Black to play and win!] (;B[df]CR[df] ;W[ef]CR[ef] (;B[cg]CR[cg] ;W[eg]CR[eg] ;B[ac]CR[ac] ;W[dg]CR[dg] ;B[af]CR[af] ;W[ae]CR[ae] ;B[ad]CR[ad] ;W[bg]CR[bg] ;B[af]CR[af] ;W[fb]CR[fb] ;B[fa]CR[fa] ;W[ae]CR[ae] (;B[cf]CR[cf] ;W[cg]CR[cg] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae] (;B[fg]CR[fg] (;W[gf]CR[gf] ;B[af]CR[af]C[Black connects the ko and wins by one point! RIGHT]) (;W[af]CR[af] ;B[gf]CR[gf]C[This is a seki, so white can't ignore Bf1!])) (;B[gf]CR[gf] (;W[fg]CR[fg] ;B[af]CR[af]C[Black connects the ko and wins by one point! RIGHT]) (;W[af]CR[af] ;B[fg]CR[fg]C[This is a seki, so white can't ignore Bg2!]))) (;B[fg]CR[fg] ;W[cf]CR[cf] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae]C[White connects the ko - jigo!]) (;B[gf]CR[gf] ;W[cf]CR[cf] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae]C[White connects the ko - jigo!]) (;B[cg]CR[cg] ;W[cf]CR[cf] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae]C[White connects the ko - jigo!])) (;B[ac]CR[ac] ;W[cg]CR[cg] ;B[af]CR[af] ;W[ae]CR[ae] ;B[ad]CR[ad] ;W[dg]CR[dg] ;B[af]CR[af] ;W[fb]CR[fb] ;B[fa]CR[fa] ;W[ae]CR[ae] ;B[cf]CR[cf] (;W[bg]CR[bg] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae] (;B[fg]CR[fg] ;W[ff]CR[ff] ;B[af]CR[af]C[Black connects the ko and wins by one point! RIGHT]) (;B[eg]CR[eg] ;W[fg]CR[fg] ;B[af]CR[af]C[Black connects the ko and wins by one point! RIGHT])) (;W[df]CR[df] ;B[af]CR[af] ;W[db]CR[db] ;B[bg]CR[bg]C[In this position, d6 is no ko threat!]))) (;B[cg]CR[cg] ;W[df]CR[df] ;B[ac]CR[ac] ;W[dg]CR[dg] ;B[af]CR[af] ;W[ae]CR[ae] ;B[ad]CR[ad] ;W[bg]CR[bg] ;B[af]CR[af] ;W[fb]CR[fb] ;B[fa]CR[fa] ;W[ae]CR[ae] (;B[cf]CR[cf] ;W[cg]CR[cg] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae]C[White connects the ko - jigo!]) (;B[cg]CR[cg] ;W[cf]CR[cf] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae]C[White connects the ko - jigo!])) (;B[ac]CR[ac] ;W[df]CR[df] (;B[af]CR[af] ;W[ae]CR[ae] (;B[ad]CR[ad] ;W[cg]CR[cg] ;B[af]CR[af] ;W[fb]CR[fb] ;B[fa]CR[fa] ;W[ae]CR[ae]C[White connects the ko - jigo!]) (;B[cg]CR[cg] ;W[dg]CR[dg] ;B[ad]CR[ad] ;W[bg]CR[bg] ;B[af]CR[af] ;W[fb]CR[fb] ;B[fa]CR[fa] ;W[ae]CR[ae] ;B[cf]CR[cf] ;W[cg]CR[cg] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae]C[White connects the ko - jigo!])) (;B[cg]CR[cg] ;W[dg]CR[dg] ;B[af]CR[af] ;W[ae]CR[ae] ;B[ad]CR[ad] ;W[bg]CR[bg] ;B[af]CR[af] ;W[fb]CR[fb] ;B[fa]CR[fa] ;W[ae]CR[ae] (;B[cf]CR[cf] ;W[cg]CR[cg] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae]C[White connects the ko - jigo!]) (;B[cg]CR[cg] ;W[cf]CR[cf] ;B[af]CR[af] ;W[db]CR[db] ;B[cb]CR[cb] ;W[ae]CR[ae]C[White connects the ko - jigo!]))))