Daily stategy problems

Written by Super User on . Posted in Study

Daily stategy problems

opening: black to play
{"filetype": "problem"}
(;FF[4]GM[1]SZ[19]AP[SGFC:1.16]AW[cb][dc][eb][gd][co][fo][pp]
AB[cc][cd][de][ck][dq][gq][qd]C[ Black to play.  

Black should be happy about his result on the left side. Can he now switch to the right side, or is there anything else still remaining to be done on the left ?]

(;B[dh]TR[gq][fo]C[Correct Answer.  

Defending with Black 1 is the best move. This makes the exchange of the marked stones bad for White. White's two stones on the lower left are now caught between two strong black positions. <=]
TE[2])
(;B[oc]C[Failure.  

Making a corner enclosure with Black 1 in not good. Black's position on the left is too thin.]

(;W[ch]C[White will invade with 2 and ...]
(;B[fe];W[eh];B[ek];W[gh]C[... Black is left with two weak groups to defend after White 6. <=]
)
(;B[eh]LB[ch:2]C[The cap.  

Black might try to counter White's invasion at 2 by capping with 3, but ...]
;W[di];B[ek];W[ei]C[... White simply moves out into the center. <=]
))
(;W[dh]LB[bh:A]C[Too high.  

White 2 on the fourth line is too high. If Black's stones get into trouble, he can always link up at A. <=]
)))

       
invading: white to play
{"filetype": "problem"}
(;FF[4]GM[1]SZ[19]AP[SGFC:1.16]AW[cd][ed][hc][ch][qc][oc][qf]
[pf][qi]AB[jc][cj][od][nd][pd][qe][re]LB[od:1]TR[oc]C[White to play.  

Connecting with Black 1 is an obvious move. In response, White has two possibilities. Where are they ?]

(;W[nc]LB[nb:A]C[Correct Answer.  

White can play either 1 or A. Both of these moves are joseki. <=]
TE[2])
(;W[pc]C[Failure.  

Connecting at 1 is heavy.];B[nc]C[Black plays 2 and, ...]
(;W[nb];B[mb];W[oa]LB[nb:3]C[... after 3 and 5, ...];B[pb];W[qb]
;B[sb]LB[pb:6]C[... kills White with 6 and 8. <=])
(;W[nb]C[Correct Answer.  

Also correct. <=]TE[2])
(;W[rb]C[White 3 here is better, she just manages to live. <=]
)))

       
attacking: black to play
{"filetype": "problem"}
(;FF[4]GM[1]SZ[19]AP[SGFC:1.16]AW[fq][dr][cr][cq][cp][cn][jq]
[jp][lp][ln][jn][jl][kl][mg][lf][mi][lk][mk][po][qp][qm][ql]
[qk]AB[dd][dp][do][dq][eq][er][fp][ip][iq][io][lm][ll][kk][kj]
[kh][pd][og][pj][pk][pl][nl][on][oo][oq]TR[kk][kj][kh][lf][mg]
[mi][mk][lk]C[Black to play.  

Both the black and white marked stones are floating in the center. It is Black's move. What should he do ?]

(;B[jf]C[Correct Answer.  

Black should attack with the knight's move of 1.]TE[2];W[ld]
C[After the exchange of 2 ...];B[jd]C[... for Black 3, ...]
;W[nd]C[... White makes shape with 4. but ...];B[pc]C[... Black secures the corner and a thick position with 5. White is in trouble. <=]
)
(;B[ld]C[Failure.  

Black 1 is in the wrong direction.];W[jf]C[It induces White to save her stones, while leaving Black's stones seriously injured. <=]
))