Problem 11251 goproblems.com

Hello, today I had my last statistics lesson. Well I hope it was the last one (if I dont pass my statistics exams I will have to do the course again). It was about indexes, there were two types of them and by mutliplying you can get some third one. As usual I was bored and was thinking about some go and goproblems and suddenly found this position. Finding the solution took me about one hour so I think this problem is quite comlicated - there are several tesujis available and it is hard to pick the one which will serve you best (at least if you want to be really precise). The comments with score I wrote for some moves are without komi, just points on the board plus prisoners. After I came to my room and run MutliGo to check my solutions, I found that if you play optimally, you will win by 0,5 points if white had 6,5 komi and if there were no prisoners at the beginning. So.. 6,5 KOMI, 0 PRISONERS EACH, BLACK TO PLAY AND WIN !!


Author	Field Mouse	Created	2008-05-06
Difficulty	9 dan (history)	Source	My last statistics lesson!
AVG solve time	66 sec	Stars	3.83 (6 votes)
User attempts	16 / 298	Collections	9*9 games, Stories
Genre	best move	Your attempts	N/A
Similar problems
Created	2008-05-06
Source	My last statistics lesson!
Stars	3.83 (6 votes)
Collections	9*9 games, Stories
Your attempts	N/A

(;SZ[9]AW[fh]AW[gf]AW[gd]AW[gc]AB[fb]AB[fc]AB[fd]AB[ec]AB[dd]AB[ce]AB[be]AB[af]AB[bf]AB[ee]AB[ef]AB[eg]AB[eh]AW[eb]AW[db]AW[dc]AW[cd]AW[bd]AW[ad]AW[ae]AW[cc]AW[bb]C[Black needs to find really good continuation to win this game.]AP[goproblems] (;B[gg];W[hg] (;B[hf];W[he];B[hh];W[if] (;B[fg];W[gb] (;B[ga];W[ha];B[fa];W[hb] (;B[ih];W[fe] (;B[ff];W[ge] (;B[ea];W[da];B[ed];W[ig]C[White 16, black 23 - you won even with the 6,5 komi, good!RIGHT]) (;B[ig];W[ea];B[ed];W[hf]C[White 16, black 23 - you won even with the 6,5 komi, good!RIGHT]) (;B[ed];W[ig];B[ea];W[da]C[White 16, black 23 - you won even with the 6,5 komi, good!RIGHT])) (;B[ea];W[da];B[ed];W[ff];B[ig];W[hf]C[White 16, black 23 - you won even with the 6,5 komi, good!RIGHT]) (;B[ig];W[ea];B[ed];W[hf];B[ff];W[ge]C[White 16, black 23 - you won even with the 6,5 komi, good!RIGHT]) (;B[ed];W[ea] (;B[ff];W[ge];B[ig];W[hf]C[White 16, black 23 - you won even with the 6,5 komi, good!RIGHT]) (;B[ig];W[hf];B[ff];W[ge]C[White 16, black 23 - you won even with the 6,5 komi, good!RIGHT]))) (;B[fe];W[ih];B[ge];W[hi];B[gh];W[ea];B[gi];W[hf];B[ii];W[ig] (;B[hi];W[hd]C[White 15, black 21.. one point behind the solution!]) (;B[id];W[ic];B[hd];W[hc]C[...]) (;B[ic];W[id]) (;B[ib];W[id])) (;B[ea];W[ih] (;B[da];W[ca];B[fe];W[hi];B[gh];W[ge];B[gi];W[ig];B[ii];W[ff];B[hi]C[White 15, black 21 - one point behind the solution!]) (;B[fe];W[hi];B[gh];W[ge];B[da];W[ca];B[gi];W[ig];B[ii];W[ff];B[hi]C[White 15, black 21 - one point behind the solution!]))) (;B[ih];W[fa]C[You should play this four points sente first.])) (;B[gh];W[gb];B[ga];W[ha];B[fa];W[ib];B[ih];W[ff] (;B[fg];W[fe];B[ig];W[ea];B[ed];W[hf]C[White 17, black 22.]) (;B[ig];W[fg];B[hf];W[fi];B[ie];W[id]C[White is ok.]))) (;B[fg];W[hh];B[hb];W[gh];B[hc];W[hd];B[gb];W[ei] (;B[di];W[fi] (;B[dh];W[ic];B[ib];W[id]C[Black could do better!]) (;B[id];W[dh];B[ie];W[hf]C[Too bad.])) (;B[id];W[dh]C[You could do better.])) (;B[hh];W[gh];B[fg];W[hi] (;B[hf];W[ih];B[ge];W[he];B[ff];W[if];B[hb];W[ei];B[di];W[fi];B[dh];W[gb];B[ga];W[hd];B[gf];W[ie];B[ic];W[ea];B[fa];W[hc];B[ha];W[ib];B[ia]C[The score on the board is 12 white - 17 black. You could do better.]) (;B[ih];W[ig];B[hf];W[ii];B[ge];W[he];B[ff];W[if] (;B[hd];W[gf];B[hc];W[fe];B[gb];W[ge] (;B[fi];W[id];B[ib];W[fa];B[ga];W[ea];B[ic];W[ie];B[ei];W[gi]C[White 15, black 20. You could do better!]) (;B[id];W[hb];B[ha];W[ei];B[di];W[fi];B[dh];W[fa];B[ib];W[ie]C[White 16, black 19.])) (;B[hb];W[fi] (;B[ei];W[gb];B[ga];W[hd];B[gf];W[ea];B[fa]C[A bit worse than the solution.]) (;B[hd];W[gf];B[hc];W[fe];B[ei];W[ge];B[gb];W[fa];B[ga];W[ea];B[id];W[ie]C[White 16, black 21.])))) (;B[gh];W[hh];B[ff];W[ge];B[hb];W[gi];B[fg];W[gb];B[ga];W[hc] (;B[fi];W[ib];B[ha];W[ea];B[fa];W[hi];B[fe]C[White 17, black 19.]) (;B[ha];W[fi];B[ei];W[hi];B[ic];W[id];B[ib];W[ea];B[fa];W[ie]C[White 15, black 17.])) (;B[hb];W[fg]TR[gg]TR[hg]C[The marked exchange was clearly bad.]) (;B[ff];W[ge] (;B[gh];W[hh];B[hb];W[gi];B[fg];W[gb];B[ga];W[hc] (;B[fi];W[ib];B[ha];W[ea];B[fa];W[hi];B[fe]C[White 17, black 19.]) (;B[ha];W[fi];B[ei];W[hi];B[ic];W[id];B[ib];W[ea];B[fa];W[ie]C[White 15, black 17.])) (;B[hh];W[gh];B[hi];W[fg];B[fi];W[gb];B[ga];W[ha];B[fa];W[hb]C[You could do better.]))) (;B[hb];W[gg] (;B[gb];W[ic];B[hc];W[hd];B[ib];W[id];B[fi];W[gi];B[ei];W[ge];B[ea];W[da];B[fa];W[gh]C[White 17, black 19]) (;B[hc];W[hd];B[id];W[ie];B[ic];W[hf];B[fi];W[gi];B[ei];W[gb];B[ga];W[ge];B[fg];W[ea];B[fa];W[gh]C[White 16, black 19.]) (;B[he];W[ge] (;B[hc];W[hd];B[id];W[gb];B[ga];W[ic];B[ib];W[ha];B[fa];W[hf]C[You could do better.]) (;B[id];W[ic];B[hc];W[hd];B[ib];W[gb];B[ga];W[ha];B[fa];W[hf]C[You could do better.]) (;B[ic];W[id];B[hd];W[hc];B[ie];W[hf];B[gb];W[if]C[You could do better.]) (;B[hd];W[hc];B[ic];W[gb];B[ga];W[id];B[ie];W[hf];B[ha];W[if]C[You could do better.]))) (;B[he];W[ge]C[This move does not help you.]) (;B[gh];W[hh];B[gg];W[hg];B[ff];W[ge];B[hb];W[gi];B[fg];W[gb];B[ga];W[hc] (;B[fi];W[ib];B[ha];W[ea];B[fa];W[hi];B[fe]C[White 17, black 19.]) (;B[ha];W[fi];B[ei];W[hi];B[ic];W[id];B[ib];W[ea];B[fa];W[ie]C[White 15, black 17.])) (;B[fg];W[gg];B[gh];W[hh];B[fi];W[gb];B[ga];W[ha];B[fa];W[hb];B[hi];W[ih]C[You could do better!]))