For lessons, as well as threads about specific moves, and anything else worth studying.
Kirby
Honinbo
Posts: 9553 Joined: Wed Feb 24, 2010 6:04 pm
GD Posts: 0
KGS: Kirby
Tygem: 커비라고해
Has thanked: 1583 times
Been thanked: 1707 times
Post
by Kirby » Sun Aug 14, 2011 7:20 am
To me, more impressive than the problem is that Herman missed something...
be immersed
Shaddy
Lives in sente
Posts: 1206 Joined: Sat Apr 24, 2010 2:44 pm
Rank: KGS 5d
GD Posts: 0
KGS: Str1fe, Midorisuke
Has thanked: 51 times
Been thanked: 192 times
Post
by Shaddy » Sun Aug 14, 2011 6:42 pm
Perhaps, Kirby, on seeing the solution you'll realise why: it's a really hard-to-find move if you're not looking specifically for it.
The solution:
This is one ordering, it seems other orders are also possible
$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . X X . X X X O O O . . | $$ | . . . . . . . . . O 7 O O O B B O . . | $$ | . . . , . . . O . . 0 8 5 X O B O . . | $$ | . . . . . . O . X . . 9 3 2 O B . . . | $$ | . . . . . . . X . . . . 6 1 O B . O . | $$ | . . . . . . . . . . . . . . 4 . . . . | $$ ---------------------------------------
Click Here To Show Diagram Code [go]$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . X X . X X X O O O . . | $$ | . . . . . . . . . O 7 O O O B B O . . | $$ | . . . , . . . O . . 0 8 5 X O B O . . | $$ | . . . . . . O . X . . 9 3 2 O B . . . | $$ | . . . . . . . X . . . . 6 1 O B . O . | $$ | . . . . . . . . . . . . . . 4 . . . . | $$ ---------------------------------------[/go]4 cannot capture, because black will connect underneath and live.
$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . 5 . . . . . . . . | $$ | . . . . . . . . X X 2 X X X O O O . . | $$ | . . . . . . . . 6 O X O O O B B O . . | $$ | . . . , . . . O . 1 O O X X O B O . . | $$ | . . . . . . O . X 7 3 X X O O B . . . | $$ | . . . . . . . X 8 . . . O X O B . O . | $$ | . . . . . . . . 9 . . . . 0 O . . . . | $$ ---------------------------------------
Click Here To Show Diagram Code [go]$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . 5 . . . . . . . . | $$ | . . . . . . . . X X 2 X X X O O O . . | $$ | . . . . . . . . 6 O X O O O B B O . . | $$ | . . . , . . . O . 1 O O X X O B O . . | $$ | . . . . . . O . X 7 3 X X O O B . . . | $$ | . . . . . . . X 8 . . . O X O B . O . | $$ | . . . . . . . . 9 . . . . 0 O . . . . | $$ ---------------------------------------[/go]4 fills. 8 is the strongest resistance for White: it breaks the ladder on the left and stops black's snapback on the right. Black can now only get ko.
tchan001
Gosei
Posts: 1582 Joined: Wed Apr 21, 2010 6:44 pm
GD Posts: 1292
Location: Hong Kong
Has thanked: 54 times
Been thanked: 534 times
Contact:
Post
by tchan001 » Sun Aug 14, 2011 7:31 pm
Actually Shaddy, there is another line for Black which prevents the placement of your "strongest resistance for white" at j2. In the second diagram, Black can play 1 at k2 instead of k4. But the result will still be ko as per your line.
Let me show you my solutions sgf which incorporates the works for this problem including the missing Black stone in Igo Hatsuyoron (from newest Chinese edition). Of course, the ideas are not really mine as I'm just a weak kyu
(;GM[1]FF[4]SZ[19]GN[]PL[B]CR[oo][po][pp][pq][pr]AW[on][pn][qn][jo][lo][mo][no][qo][hp][op][qp][gq][oq][or][rr]AB[in][jn][ln][mn][nn][oo][po][np][pp][iq][pq][hr][pr][jl] (;B[nr]C[Right];W[nq] (;B[mq] (;W[os]C[Right] (;B[mp]C[Right];W[mr] (;B[ko]C[Right];W[lp];B[lq];W[kp];B[kq] (;W[kn] (;B[jq] (;W[ir]C[Right] (;B[is]C[Right];W[qr];B[jp];W[ko];B[km];W[io];B[ho];W[ip];B[gp];W[hq];B[fq] ;W[gr] ;B[gs]C[Ko]) (;B[jr]C[Wrong];W[qr];B[jp];W[ko];B[km];W[io];B[ho];W[ip];B[gp];W[hq];B[fq] ;W[gr]) (;B[hs]C[Wrong] (;W[qr]C[Wrong];B[jp];W[ko];B[km];W[io];B[ho];W[ip];B[gp];W[hq];B[fq];W[gr]) (;W[is]C[Right])) (;B[hq]C[Wrong];W[qr];B[ms];W[ns];B[ls];W[lr];B[ks];W[kr];B[js];W[jr];B[is] ;W[hs])) (;W[io]C[Wrong];B[ms];W[ns];B[ls];W[lr];B[ks];W[kr];B[js];W[jr];B[is]) (;W[qr]C[Wrong];B[jp];W[ko];B[km];W[io];B[ho];W[ip];B[gp];W[hq];B[fq])) (;B[jr] (;W[lr];B[jp];W[ko];B[km];W[io];B[ho];W[ip];B[gp];W[hq];B[fq] ;W[gr];B[fr] ;W[jq]C[Ko]) (;W[ip];B[ms];W[ns];B[ls];W[lr];B[ks]))) (;W[jp]C[Wrong];B[ip];W[kn];B[io];W[km];B[jq];W[ko];B[ms];W[ns];B[ls];W[lr] ;B[ks];W[kr];B[js];W[jr];B[is])) (;B[lr]C[Wrong];W[qr])) (;B[ps]C[Wrong];W[mp];B[ns];W[np];B[ko];W[lp];B[lq];W[kp];B[kq];W[kn];B[jp] ;W[ko];B[km];W[io];B[ho];W[ip];B[gp];W[hq];B[fq];W[gr];B[fr] ;W[jq])) (;W[mp]C[Wrong];B[os];W[np];B[ko];W[lp];B[lq];W[kp];B[kq] (;W[kn];B[jp];W[ko];B[io];W[km];B[ll];W[lm];B[ml]) (;W[jp];B[ip];W[kn];B[io];W[km];B[jq];W[ko];B[ll]))) (;B[mp]C[Wrong];W[mq];B[lp];W[ko];B[lq];W[mr]) (;B[os]C[Wrong];W[mq];B[mr];W[lq];B[lr];W[kr];B[kq];W[jr];B[kp];W[ko];B[io] ;W[ls];B[ns] ;W[qr]C[White has more liberties])) (;B[ko]C[Wrong];W[mq]) (;B[lp]C[Wrong];W[ko];B[nq];W[nr];B[mr];W[mq];B[mp];W[lq];B[kp];W[lr]))
Shaddy
Lives in sente
Posts: 1206 Joined: Sat Apr 24, 2010 2:44 pm
Rank: KGS 5d
GD Posts: 0
KGS: Str1fe, Midorisuke
Has thanked: 51 times
Been thanked: 192 times
Post
by Shaddy » Sun Aug 14, 2011 10:17 pm
Hm, I'd missed that before. Thanks, tchan!
HermanHiddema
Gosei
Posts: 2011 Joined: Tue Apr 20, 2010 10:08 am
Rank: Dutch 4D
GD Posts: 645
Universal go server handle: herminator
Location: Groningen, NL
Has thanked: 202 times
Been thanked: 1086 times
Post
by HermanHiddema » Mon Aug 15, 2011 1:49 am
How did I ever miss that?!
Great problem
I was already exploring variants like this:
$$B $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . X X . X X X O O O . . | $$ | . . . . . . . . . O . O O O B B O . . | $$ | . . . , . . . O . . . . . X O B O . . | $$ | . . . . . . O . X . . 2 4 5 O B . . . | $$ | . . . . . . . X . . . 3 6 1 O B . O . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------
Click Here To Show Diagram Code [go]$$B $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . X X . X X X O O O . . | $$ | . . . . . . . . . O . O O O B B O . . | $$ | . . . , . . . O . . . . . X O B O . . | $$ | . . . . . . O . X . . 2 4 5 O B . . . | $$ | . . . . . . . X . . . 3 6 1 O B . O . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]