Problem 2998 goproblems.com


Author	WTD	Created	2003-09-26
Difficulty	8 dan (history)	Source	Basic Techniques of Go
AVG solve time	45 sec	Stars	3.07 (15 votes)
User attempts	1240 / 4222	Collections	N/A
Genre	best move	Your attempts	N/A
Similar problems
Created	2003-09-26
Source	Basic Techniques of Go
Stars	3.07 (15 votes)
Collections	N/A
Your attempts	N/A

(;SZ[19]AW[gn]AW[in]AW[ln]AW[nn]AW[ho]AW[jo]AW[lo]AW[mo]AW[hp]AW[mp]AW[hq]AW[mq]AW[hr]AW[lr]AW[ms]AB[fn]AB[on]AB[eo]AB[go]AB[no]AB[oo]AB[gp]AB[np]AB[gq]AB[jq]AB[nq]AB[er]AB[gr]AB[jr]AB[mr]AB[nr]TR[jq]TR[jr]C[Black to connect the marked stones to the outside, unconditionally.]GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2]RU[Japanese]KM[0.00] (;B[lq];W[kq] (;B[ls];W[ks] (;B[js];W[gs] (;B[kr];W[lp] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[fs];W[hs] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[ls];W[fr]C[What if White plays a threat like this?] (;B[fq];W[ks]C[Play at T (H6) for a small ko threat.]LB[hn:T] (;B[ns]C[White cannot connect at M1.RIGHT]) (;B[hn];W[ls]C[You did not need a ko threat to connect.])) (;B[ns]C[The group was safe already, you just wasted a move.]) (;B[ks]C[The group was safe already, you just wasted a move.]) (;B[lq]C[The group was safe already, you just wasted a move.]) (;B[jp];W[es]C[Not big enough.]) (;B[kp];W[lq] (;B[fq];W[ks]C[Ko]) (;B[ns];W[es]C[The group was safe already, you just wasted a move.]))))) (;B[fs];W[hs];B[kr];W[lp] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[ls];W[fr]C[What if White plays a threat like this?] (;B[fq];W[ks]C[Play at T (H6) for a small ko threat.]LB[hn:T] (;B[ns]C[White cannot connect at M1.RIGHT]) (;B[hn];W[ls]C[You did not need a ko threat to connect.])) (;B[ns]C[The group was safe already, you just wasted a move.]) (;B[ks]C[The group was safe already, you just wasted a move.]) (;B[lq]C[The group was safe already, you just wasted a move.]) (;B[jp];W[es]C[Not big enough.]) (;B[kp];W[lq] (;B[fq];W[ks]C[Ko]) (;B[ns];W[es]C[The group was safe already, you just wasted a move.])))) (;B[ns];W[kr])) (;B[kr];W[lp] (;B[js];W[hs] (;B[ns]C[RIGHT]) (;B[ls];W[gs]C[What if White plays a reasonable threat, like G1?] (;B[fs];W[ks]LB[hn:T]C[Play at T (H6) if you think you need a threat. The threat is not very big.] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[jp];W[ls]) (;B[kp];W[lq]C[Just ko]) (;B[hn];W[ls]C[You did not need a threat to connect. Now it's too late.])) (;B[ns]C[The group was safe already, you just wasted a move.]) (;B[ks]C[The group was safe already, you just wasted a move.]) (;B[jp];W[es]C[Not big enough; F1 would have been at least 4 points worth.]) (;B[lq]C[The group was safe already, you just wasted a move.])) (;B[kp];W[lq]C[Only ko])) (;B[hs];W[is] (;B[js];W[jp];B[ns];W[ir];B[ls];W[iq]C[Only ko]) (;B[gs];W[ls]) (;B[ir];W[jp];B[js];W[iq]C[Ko]) (;B[ns];W[ir] (;B[js];W[jp];B[ls];W[iq]C[Only ko]) (;B[ls];W[js]C[Ko])))) (;B[hs];W[is] (;B[kr];W[lp] (;B[js];W[jp];B[ns];W[ir];B[ls];W[iq]C[Only ko]) (;B[gs];W[ls]) (;B[ir];W[jp];B[js];W[iq]C[Ko]) (;B[ns];W[ir] (;B[js];W[jp]) (;B[ls];W[js]C[Ko]))) (;B[js];W[ir];B[kr];W[lp] (;B[ls]) (;B[ns];W[jp])) (;B[ir];W[gs];B[kr];W[lp];B[js];W[jp];B[hs];W[iq];B[ls]C[Ko]))) (;B[kr];W[lp] (;B[js];W[gs] (;B[ls];W[ks] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[fs];W[hs] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[ls];W[fr]C[What if White plays a threat like this?] (;B[fq];W[ks]C[Play at T (H6) for a small ko threat.]LB[hn:T] (;B[ns]C[White cannot connect at M1.RIGHT]) (;B[hn];W[ls]C[You did not need a ko threat to connect.])) (;B[ns]C[The group was safe already, you just wasted a move.]) (;B[ks]C[The group was safe already, you just wasted a move.]) (;B[lq]C[The group was safe already, you just wasted a move.]) (;B[jp];W[es]C[Not big enough.]) (;B[kp];W[lq] (;B[fq];W[ks]C[Ko]) (;B[ns];W[es]C[The group was safe already, you just wasted a move.]))))) (;B[fs];W[hs];B[ls];W[ks]LB[hn:T]C[Play at T (H6) if you think you need a threat. The threat is not very big.] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[jp];W[ls]) (;B[kp];W[lq]C[Just ko]) (;B[hn];W[ls]C[You did not need a threat to connect. Now it's too late.]))) (;B[ls];W[ks] (;B[js];W[hs] (;B[ns]C[RIGHT]) (;B[ls];W[gs]C[What if White plays a reasonable threat, like G1?] (;B[fs];W[ks]LB[hn:T]C[Play at T (H6) if you think you need a threat. The threat is not very big.] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[jp];W[ls]) (;B[kp];W[lq]C[Just ko]) (;B[hn];W[ls]C[You did not need a threat to connect. Now it's too late.])) (;B[ns]C[The group was safe already, you just wasted a move.]) (;B[ks]C[The group was safe already, you just wasted a move.]) (;B[jp];W[es]C[Not big enough; F1 would have been at least 4 points worth.]) (;B[lq]C[The group was safe already, you just wasted a move.])) (;B[kp];W[lq]C[Only ko])) (;B[hs];W[is] (;B[js];W[jp];B[ns];W[ir];B[ls];W[iq]C[Only ko]) (;B[gs];W[ls]) (;B[ir];W[jp];B[js];W[iq]C[Ko]) (;B[ns];W[ir] (;B[js];W[jp]) (;B[ls];W[js]C[Ko]))))) (;B[js];W[gs] (;B[ls];W[ks] (;B[kr];W[lp] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[fs];W[hs] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[ls];W[fr]C[What if White plays a threat like this?] (;B[fq];W[ks]C[Play at T (H6) for a small ko threat.]LB[hn:T] (;B[ns]C[White cannot connect at M1.RIGHT]) (;B[hn];W[ls]C[You did not need a ko threat to connect.])) (;B[ns]C[The group was safe already, you just wasted a move.]) (;B[ks]C[The group was safe already, you just wasted a move.]) (;B[lq]C[The group was safe already, you just wasted a move.]) (;B[jp];W[es]C[Not big enough.]) (;B[kp];W[lq] (;B[fq];W[ks]C[Ko]) (;B[ns];W[es]C[The group was safe already, you just wasted a move.]))))) (;B[fs];W[hs];B[kr];W[lp]) (;B[ns];W[kr])) (;B[fs];W[hs] (;B[ls];W[ks];B[kr];W[lp]) (;B[kr];W[lp];B[ls])) (;B[kr];W[lp] (;B[ls];W[ks] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[fs])) (;B[fs];W[hs];B[ls]))) (;B[hs];W[is];B[js];W[ir] (;B[kr];W[lp];B[ls];W[ks];B[ns];W[jp]) (;B[ls];W[ks];B[kr];W[lp] (;B[ls]) (;B[ns])))) (;B[js];W[gs] (;B[lq];W[kq] (;B[ls];W[ks];B[fs]C[RIGHT]) (;B[kr];W[lp])) (;B[kr];W[lq];B[ls];W[ks]C[Only ko.]) (;B[ls];W[ks] (;B[kr];W[lq];B[ls]C[Only ko.]) (;B[lq];W[kq] (;B[kr];W[lp] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[fs];W[hs] (;B[ns]C[White cannot play M1 and Black is connected.RIGHT]) (;B[ls];W[fr]C[What if White plays a threat like this?] (;B[fq];W[ks]C[Play at T (H6) for a small ko threat.]LB[hn:T] (;B[ns]C[White cannot connect at M1.RIGHT]) (;B[hn];W[ls]C[You did not need a ko threat to connect.])) (;B[ns]C[The group was safe already, you just wasted a move.]) (;B[ks]C[The group was safe already, you just wasted a move.]) (;B[lq]C[The group was safe already, you just wasted a move.]) (;B[jp];W[es]C[Not big enough.]) (;B[kp];W[lq] (;B[fq];W[ks]C[Ko]) (;B[ns];W[es]C[The group was safe already, you just wasted a move.]))))) (;B[fs];W[hs];B[kr];W[lp]) (;B[ns];W[kr])) (;B[fs];W[hs] (;B[kr];W[lq];B[ls]C[Only ko.]) (;B[lq];W[kq];B[kr];W[lp]))) (;B[fs];W[hs] (;B[lq];W[kq] (;B[ls];W[ks]) (;B[kr];W[lp])) (;B[ls];W[ks] (;B[kr];W[lq];B[ls]C[Only ko.]) (;B[lq];W[kq]))) (;B[hs];W[is] (;B[lq];W[kq] (;B[ls];W[ks] (;B[kr];W[lp] (;B[ns]C[RIGHT]) (;B[ls]C[RIGHT])) (;B[ns];W[kr])) (;B[kr];W[lp];B[ls];W[ks];B[ns]C[RIGHT]) (;B[ns];W[ls])) (;B[kr];W[lq];B[ls];W[ks]C[Ko]) (;B[ls];W[ks];B[kr];W[lq]C[Ko]))) (;B[ls];W[ks] (;B[lq];W[js] (;B[kr];W[is];B[ls]C[Only ko.]) (;B[is];W[hs];B[ir];W[kq];B[kr];W[lp];B[ns];W[jp];B[ls];W[ks];B[lq]C[A difficult ko for White to win, admittedly, but still not unconditional.])) (;B[js];W[gs] (;B[kr];W[lq];B[ls]C[Only ko.]) (;B[lq];W[kq]) (;B[fs];W[hs] (;B[kr];W[lq];B[ls]C[Only ko.]) (;B[lq];W[kq]))) (;B[hs];W[is];B[js];W[ir] (;B[lq];W[kq];B[kr];W[lp] (;B[ls]) (;B[ns])) (;B[kr];W[lq]C[Only ko.]))) (;B[hs];W[is]C[Give up now. The best from this is ko.] (;B[ir];W[gs];B[js] (;W[ls]C[Only ko.CHOICE]) (;W[lq]C[Only ko.CHOICE]) (;W[hs] (;B[lq];W[kq];B[kr];W[lp];B[ls];W[ks];B[ns];W[jp];B[ls];W[iq]C[Only ko.]) (;B[ls];W[ks];B[lq];W[kq];B[kr];W[lp];B[ns];W[jp];B[ls];W[iq]C[Only ko.]))) (;B[js];W[ir] (;B[lq];W[kq] (;B[kr];W[lp];B[ls];W[ks];B[ns]) (;B[ls];W[ks])) (;B[ls];W[ks] (;B[lq];W[kq]) (;B[kr];W[lq]C[Only ko.])))))