Problem 21327 goproblems.com


Author	nimbim	Created	2016-09-30
Difficulty	6 dan (history)	Source	problem 21310
AVG solve time	94 sec	Stars	3 (1 votes)
User attempts	56 / 303	Collections	Ko / Ko Threats, Life and Death
Genre	life and death	Your attempts	N/A
Similar problems
Created	2016-09-30
Source	problem 21310
Stars	3 (1 votes)
Collections	Ko / Ko Threats, Life and Death
Your attempts	N/A

(;AB[bc]AB[bd]AB[ce]AB[de]AB[ee]AB[fe]AB[fd]AB[fc]AB[gc]AB[gb]AW[fb]AW[ed]AW[ec]AW[dd]AW[cd]AW[cc]AW[bb]AW[ab]AB[bf]AB[db]AW[be]C[White to play. Black has one external ko threat, White has no external ko threat.]AP[goproblems] (;W[eb];B[cb] (;W[ba] (;B[ea]C[CHOICE] (;W[fa];B[ca];W[da];B[he]C[Respond to the ko threat.]TR[ie] (;W[ie];B[ea]C[Please finish the ko. If you want to tenuki you can play at A15.] (;W[ad];B[ae];W[da]C[RIGHT]) (;W[ac];B[ae];W[da]C[RIGHT]) (;W[ae];B[ga];W[da]C[This situation would be worse for White, if Black could capture the ko again at some point. Under the given circumstances this answer is correct.RIGHT])) (;W[hd]C[NOTTHIS]) (;W[id]C[NOTTHIS]) (;W[jd]C[NOTTHIS]) (;W[je]C[NOTTHIS]) (;W[if]C[NOTTHIS]) (;W[jf]C[NOTTHIS]) (;W[hf]C[NOTTHIS])) (;W[ca];B[fa]C[oops]) (;W[da];B[ca];W[fa];B[ga];W[da];B[he]C[Respond to the ko threat.]TR[hd] (;W[hd];B[ea] (;W[ad];B[dc]C[oops]) (;W[ac];B[dc]C[oops])) (;W[hc]C[NOTTHIS]) (;W[ic]C[NOTTHIS]) (;W[id]C[NOTTHIS]) (;W[ie]C[NOTTHIS]) (;W[gd]C[NOTTHIS]) (;W[ge]C[NOTTHIS]))) (;B[da];W[ea]TR[ac]TR[be]C[RIGHT])) (;W[ca];B[da] (;W[ba];B[fa]C[oops]) (;W[ea];B[ba]C[White can't approach.]) (;W[dc];B[ba]C[White can't approach.]) (;W[aa];B[fa]C[oops])) (;W[da];B[ca] (;W[ba];B[ea];W[fa];B[ga];W[da];B[he]C[Respond to the ko threat.]TR[hd] (;W[hd];B[ea] (;W[ad];B[dc]C[oops]) (;W[ac];B[dc]C[oops])) (;W[hc]C[NOTTHIS]) (;W[ic]C[NOTTHIS]) (;W[id]C[NOTTHIS]) (;W[ie]C[NOTTHIS]) (;W[gd]C[NOTTHIS]) (;W[ge]C[NOTTHIS])) (;W[ea];B[ba]C[White can't approach.]) (;W[fa];B[ga];W[ba];B[ea] (;W[ad];B[dc]C[oops]) (;W[ac];B[dc]C[oops])) (;W[dc];B[ea]C[oops])) (;W[dc];B[fa]) (;W[fa];B[ga] (;W[ca];B[da];W[ba]C[White can't approach.]) (;W[da];B[ca];W[ba];B[ea] (;W[ad];B[dc]C[oops]) (;W[ac];B[dc]C[oops])) (;W[ba];B[da]C[White can't approach.])) (;W[ea];B[ba] (;W[ca];B[da]C[White can't approach.]) (;W[da];B[ca]C[White can't approach.]) (;W[dc];B[ca]C[White can't approach.]))) (;W[cb];B[eb]C[White has only one eye.]) (;W[ac]C[NOTTHIS]) (;W[ad]C[NOTTHIS]) (;W[ea];B[eb]C[oops]) (;W[ca];B[eb]C[White has only one eye.]) (;W[da];B[eb]C[oops]) (;W[fa];B[eb]C[oops]) (;W[ba];B[eb]C[White has only one eye.]))