(;GM[1]FF[4]SZ[19]AP[SmartGo:3.1.4]CA[shift_jis]
GN[30]
PW[AlphaGo]
PB[AlphaGo]
EV[AlphaGo selfplay]RO[30]
KM[7.5]
RE[W+R]
RU[Chinese]MU[1]MU[0];B[qd];W[dp];B[pq];W[dc];B[de];W[ce];B[cf];W[cd];B[df]
;W[fc];B[cn]
(;W[fq]
C[White could have pincered, which reminds me of a joseki that AGMaster and AGZero played several times (see var). ]
;B[cp];W[cq];B[bq]
(;W[dr]
C[I still don't like this move, and I want to play the normal joseki (see var). ]
;B[bo];W[do];B[dl]LB[dn:A]
C[In a position where Black A might be called the normal move, Black 19 was a light move that loosely controlled the left side.]
(;W[oc]
C[White has some aji with the atari on the left (see var). ]
(;B[pn]
C[The var shows Black playing a one space shimari, which is better for defending the corner territory, but gives White more space to invade the right side. ]
(;W[pf]
C[AG usually likes to press with a knight's move (see var), and in this set of self-played games it played the Taisha in this game only. AG played this move a number of times in the Master games against human pros. ]
;B[od];W[pd];B[pe];W[pc];B[qe];W[oe];B[nd];W[qc];B[qf]LB[of:A][ne:B][pg:C]
C[This joseki has been studied deeply by top players since the 19th century. White's next move is a branching point. White A is usually called the mainline. White B or C are both more forceful than A, and attempt to put more pressure on Black, sometimes involving ladders. ]
(;W[ne]
C[This is the move that was played by Genan in the famous ear-reddening game, played in 1846. If White had connected with this move, Black would have probably just sacrificed two stones on the upper side (see var). ]
(;B[nc]
C[While extending on the fourth line has been the most popular move in the past, it is actually safer to cover on the third line as in the game. The game move has become mainline in recent years. The var shows how the local fight was handled in the ear-reddening game.]
;W[pg];B[ob];W[pb];B[nb]
(;W[rc]
C[The var shows how White could haved lived in the corner. The game move is not alive yet, but White will have an advantage in most semeais with a Black group, and thus gets a chance to attack and put pressure on Black for awhile before defending the corner. ]
;B[rh];W[qg];B[rg];W[rd];B[re];W[qi]LB[se:A]
C[I cannot find any special reason for White to omit the atari at A, but it seems to make little difference, in that I expect the same sequence on the right to follow anyway. ]
;B[ri];W[qj];B[rj];W[qk];B[rl];W[le];B[kc];W[ra];B[ql];W[ok];B[hc]
C[Black A was a big move that made life for Black's group on the upper side. ]
LB[hc:A];W[oo]LB[dj:A]
C[This move was completely unexpected, and I would have probably oplayed something like an invasion at A. ]
(;B[ol]
C[I think I see what White was trying to accomplish here, so to demonstrate that idea, I added a var with Black simply protecting. ]
;W[se];B[rf];W[nk];B[cr];W[dq];B[nl]
C[Black is trying a splitting attack in the center. The idea if White continues to extend is to push a few times and then swallow up the marked stone, or to cut as soon as White plays a hane. ]
TR[oo];W[ml];B[mk];W[pl]
C[This is a vital point that gives Black bad shape, while a Black play at A would have given White bad shape. ]
LB[pk:A];B[pm];W[pk];B[mn];W[ll]
(;B[mp]
C[Later in the game we will see how White had a lot of fun in the LR corner area, so I added a var with a safer move for Black. ]
;W[id]
C[How to protect, maybe Black A?]LB[jc:A];B[lk]
C[Black attacks in the center. ]
(;W[kl]
C[The var shows White playing a hane.];B[kk];W[jk]
(;B[li]
C[The good shape move. Black must gather strength before cutting (see var). ]
;W[il]
(;B[oh]
C[This was not the expected vital point (see var). ]
(;W[nh]
C[White counter-attacks strongly. Otherwise, if White simply defends, Black's stone will be hitting a vital point (see var). ]
;B[ng];W[mh]
(;B[qh]
C[This is better than cutting (see var). ];W[mg];B[nj];W[mj]
(;B[kh]
C[Black must escape in the center first (see var).];W[jj];B[ki];W[oi]
(;B[pi]
C[Black's group in the center is still in danger (see var). ];W[ph];B[of]
;W[pj];B[me]LB[pi:A][ih:B][jg:C]TR[ne:oe]
C[With the forceful play at A, Black has captured the two cutting stones, thus settling Black's group on the upper side. This reduces the value of the local fight, although I would still want to attack with White B or C. ]
(;W[oq]
C[White switches to the LR corner, instead of going after the Black group (see var). ]
(;B[or]
C[A var is added to show how Black has weak shape. ];W[nn];B[mm];W[nm];B[om]
;W[mo];B[lo];W[no];B[kn];W[nr]
C[White covers on the second line to set up a ko. ];B[op];W[np];B[nq];W[mq]
;B[lp];W[oq];B[jm];W[pp];B[jl]TR[kl:ml]
C[The ko was worth something like 50 points. Black captured the marked stones for about 10 points in territory, saving the Black group in the center and creating a strong position in the center. After this trade, White has a lead in territory. ]
;W[co]
(;B[fk]
C[Black plays away from the corner in an attempt to get territory on the side and in the center. ]
;W[cm]
C[White attacks strongly];B[dn];W[dm];B[en];W[bm];B[bn];W[em];B[fm];W[el]
;B[gn];W[dj]
(;B[ed]
C[I would simply take away White's base on the side (see var). ];W[ec];B[ge]
;W[ch]
C[White takes the side territory. ];B[ei];W[gd]LB[gd:A]
C[Starting with A, White threatens to capture Black on the upper side, forcing Black to protect and reduces Black's territory in the center in the process. ]
;B[hd];W[he];B[mi];W[og];B[nf];W[ni];B[hf];W[ie];B[ic];W[jg];B[gf];W[kg]
;B[ih];W[kd];B[lc];W[qp]
C[White A is the last big move, and White has secured a solid lead. ]LB[qp:A]
;B[bj]LB[bj:A]
C[While Black A is a good shape, it doesn't really accomplish anything, or at least that's what I thought. ]
(;W[di]
C[This move allowed Black to complicate things, although maybe AG just had it all calculated and didn't care (see var). ]
;B[bh];W[bg];B[ci];W[cj];B[bi]
(;W[fj]
C[White cannot capture the four Black stones (see var). ];B[bf];W[fl];B[ek]
;W[ej];B[bc]
C[Setting up some aji in the corner. ];W[bd];B[gk];W[gl];B[dk];W[ck];B[hj]
LB[ei:A][bl:B][hm:C]
C[Yes, this all looks confusing and dangerous, but it is not a disaster for White yet. White has potential eyes at A, B, and C, and will have some chances to attack Black's weak connections. ]
;W[cg];B[ad]
C[Black uses the corner aji to get a stone at A. ]LB[af:A];W[ae];B[af];W[ac]
LB[ag:A][dh:B]
C[A and B are miai, so the four Black stones are linked up for now. ]
(;B[hm]
C[The var shows an example of why Black needs to fix its shape in the center.]
;W[hl];B[ii]LB[hm:A][eh:B][gh:C]
C[Black played the peep at A to deny White the option of creating an eye at that point. White already has one eye in the center with the forcing moves at B and C. ]
(;W[im]
C[We are heading toward a ko in the center, but first to demonstrate that White cannot capture four Black stones on the left (see var). ]
;B[in];W[gm];B[fn];W[hn];B[ho];W[go]
C[Cutting at A would have been a more forceful way to execute the ko, but the game move works also. ]
LB[io:A];B[hm];W[eg];B[ag];W[hn]
C[White has enough ko threats, and eventually Black will need to protect at A. White will then win the semeai against Black's group in the corner. ]
LB[io:A];B[cl];W[bk];B[hm];W[gh];B[hh];W[hn];B[bl];W[io]
C[After all that excitement, White finally decides to simplify the game by finishing the ko. ]
;B[hm];W[hk]
C[White had this final ko threat ready. ];B[gj];W[hn];B[am];W[jn];B[km];W[kq]
;B[jp];W[aj];B[dg];W[dh];B[ah]
(;W[bp]
C[There was still a ko on the left, but White is playing relatively simply (see var). ]
;B[al];W[jq]
(;B[ip]
C[One final semeai (see var). ];W[hp];B[iq];W[rn];B[ap];W[jo];B[kp];W[ir]
;B[hr];W[br];B[ar];W[aq];B[gb];W[fb];B[bq];W[jr];B[lf];W[lg];B[hq];W[bs]
;B[gp];W[ho];B[ke];W[je];B[ld];W[ig];B[hg];W[aq];B[ab];W[cb];B[dd];W[be]
;B[lq];W[lr];B[ro];W[qn];B[sn];W[sm];B[so];W[qo];B[rm];W[fe];B[fd];W[gc]
;B[ee];W[rp];B[hb];W[ff];B[fg];W[sp];B[fa];W[ea];B[ga];W[ca];B[bq];W[gq]
;B[fr];W[gr];B[gs];W[er];B[fs];W[ko];B[hs];W[is];B[ln];W[aq];B[ad];W[cc]
;B[bq];W[es];B[lm];W[aq];B[mr];W[ms]
(;B[bq]
C[As Black is about to resign, I made a var at this point to show the endgame.]
;W[fo]
C[Black resigns.])
(;B[fp];W[eq];B[bq];W[fo];B[jd];W[aq];B[eb];W[db];B[bq];W[rk];B[qm];W[aq]
;B[sb];W[rb];B[bq];W[sl];B[cp];W[pa];B[eo];W[ep];B[bp];W[oa];B[na];W[oj]
;B[sj];W[sk];B[sf];W[sd]
C[This endgame sequence assumes that Black can win the ko after taking the big point at A, so this is as good as possible for Black. 
W+3/4 of a stone=2and 1/2 points]
))
(;B[hp];W[ip];B[hq];W[gp];B[jo];W[in];B[iq];W[gq];B[jr];W[kr];B[gr];W[hr]
;B[ir];W[js];B[hs];W[ks];B[is];W[fs];B[fr];W[es];B[er];W[ds];B[eq];W[gs]
C[Black loses the semeai.]))
(;W[al];B[ak];W[jc];B[jb];W[al];B[an];W[bp]
C[Locally Black is in trouble, so this is still a win for White, but Black will be playing A as a ko threat, andthis var is more complicated than the game sequence. ]
LB[ap:A]))
(;W[ag];B[bk];W[cl];B[dh];W[dg];B[eh];W[eg];B[fh];W[fg];B[gh];W[bl];B[gg]
;W[ak];B[ff];W[aj];B[ef]
C[Black wins the semeai. ]))
(;B[dh];W[gm];B[fn];W[dg];B[eh];W[gh];B[eg];W[gj];B[hk];W[hi]LB[dh:A][gh:B][ag:C]
C[In this var Black cuts at A, and White uses B as a double threat to the left side and capturing some Black stones in the center. This also indicates that before Black A, White B was already a similar double threat with the center and White C. ]
))
(;W[bf];B[dh];W[cg];B[ek];W[dk];B[ej];W[cl];B[bk]
C[From the flow of play, one might assume that White was going to caoture Black with A, but Black can easily win the semeai (and the game) in this var. ]
LB[bf:A]))
(;W[bi];B[di];W[ci];B[cj];W[dk];B[ak];W[al];B[bl];W[am];B[ck];W[cl];B[ej]
;W[bk]LB[jh:B][fo:C][bi:A]
C[If White had played at A, the best I can find for Black is this one move step ko that favors White. Since the ko is not direct, White can play ko threats such as B or C without fear. Black does not have many forcing ko threats anyway, so this is easy for White. ]
))
(;B[bi];W[ch];B[bh];W[ci];B[bj];W[fi]
C[This still looks good for White, as Black's group on the left is not very strong. ]
))
(;B[bp];W[dj];B[ge];W[fj]LB[cm:A]))
(;B[pp];W[nn];B[mm];W[nm];B[om];W[mo];B[lo];W[no];B[ln];W[lp];B[jm];W[jl]
;B[mq];W[lq];B[op];W[jo];B[kn];W[jn];B[np];W[ko];B[po];W[km];B[on];W[dj]
C[White A hits a weak point in Black's shape. Black can actually win the semeai, but White's profit and strength on the outside is more than enough to give White a safe lead.]
LB[nn:A]))
(;W[jg];B[jm];W[jl];B[ih];W[mf];B[nf];W[jh];B[kq]LB[jg:A][kq:B]
C[White's group on the right was already alive, so this is actually an example of White building territory from a strong group, which is a bad idea. If Black can make the LR corner territory, this is good for Black. ]
))
(;B[ph];W[jg];B[ii];W[ih]
C[White has captured the Black group in the center. ]))
(;B[oi];W[ki];B[mi];W[ni];B[oj];W[lh];B[lj];W[kj];B[mj];W[ph];B[pi];W[nf]
;B[rk];W[og];B[pj];W[jb]
C[White can sac seven stones to get strong influence in the center, and attack Black on the top. This is good for White. ]
))
(;B[of];W[nf];B[og];W[mg];B[oi];W[nj];B[qh];W[ih]TR[pf:pg][qg]
C[White can sac the marked stones and capture Black with a center territory. Black's upper side is still weak, and this is good for White.]
))
(;W[ng];B[ni]LB[qh:A][me:B]
C[Black is looking at cutting attacks at A or B. ]))
(;B[ng];W[mh];B[of];W[mf];B[oh];W[pi];B[mg];W[lg];B[lh];W[ni];B[kg];W[lf]
C[Black A is usually the vital point to destry White's shape, but in this case it fails by getting cut off from Black's group in the center. ]
LB[ng:A]))
(;B[jl];W[jm];B[il];W[kj];B[jj];W[ik];B[ki];W[hl]LB[jl:A][kj:B]
C[If Black immediately cuts at A, White can use the tesuji at B to capture two stones in a ladder. This is good for White. ]
))
(;W[kk];B[li];W[kl];B[ni];W[ng];B[ji];W[ic];B[ke]LB[kk:A][oh:B]
C[Playing forcefully at A seems to actually weaken White's group on the right. There is an annoying peep at B that Black can aim to play later. ]
))
(;B[np];W[nn];B[mm];W[mo];B[no];W[ln];B[on];W[lm];B[nm];W[dj]LB[np:A]
C[Black A  is safer than the game move, but it gives White an opportunity to squeeze as shown. While the game is undecided, I would be happy to play with White. ]
))
(;B[po];W[oq];B[or];W[pr];B[op];W[nq];B[nr];W[np];B[pp];W[lq];B[mr];W[kp]
;B[qr];W[dj]LB[pr:A][oo:B]
C[White's crosscut at A is a common sabaki tactic, and in this case it works well after White has played first at B. This var is clearly good for White. ]
))
(;W[rb];B[qg];W[me];B[rd];W[qa];B[kc];W[qh];B[rh];W[qi];B[ri];W[qj];B[rj]
LB[rb:A][rd:B]
C[White A is the living tesuji that we learned in basic life/death problems, but it is actually too painful for White. Black gets the forcing move at B, and the Black group on the right is healthy now. ]
))
(;B[md];W[pg];B[qg];W[me];B[ld];W[le];B[kd];W[qh];B[rh];W[ri]LB[qg:A][rh:B]
C[While the board position is different, this shows the local fight in the ear-reddening game between Shusaku and Genan. Black A was a mistake, and should have been a slide at B. Genan had a good game with White, but eventually lost in the endgame after Shusaku played the famous ear-reddening move. ]
))
(;W[of];B[qh];W[mb];B[ed];W[ec];B[ge];W[me];B[iq]TR[dc:fc][oc:qc]LB[mb:A]
C[After White plays at A, the two marked White groups on the upper side are both strong. Therefore, it is reasonable for Black to avoid a local fight and just sac two stones. ]
))
(;W[pe];B[qe];W[pf];B[qg];W[pg];B[qh];W[ph];B[pc];W[ob];B[pi];W[oi];B[oj]
;W[ni];B[pj];W[qf];B[rf];W[re];B[rd];W[nj];B[ol]LB[qo:A][qq:B][gf:C]
C[This shows a modern version of the UR corner joseki. White still has some aji with an invasion at A or B. White could continue with something like C to build up the upper side. ]
))
(;B[po];W[pe];B[qe];W[pf];B[qg];W[qm]LB[po:A][pe:B][qm:C]
C[When Black plays the shimari at A, White can press at B and still have plenty of room to invade at C later. The big shimari played in the game is better when White does something like this, but has a less secure corner territory, so the pros and cons probably balance out. ]
))
(;W[co];B[bp];W[cj];B[ej];W[cm];B[dn];W[dm];B[en];W[bm];B[em];W[bn];B[cr]
;W[dq];B[cs];W[ch]LB[co:A][cm:B][hq:C]
C[White can play the atari at A to set up an attack at B next. The Black group in the corner will die with a bent four and will eventually need an extra stone, but Black can start with the pincer at C before defending the corner. While White's play in this var is effective in erasing the left side, it's probably premature in this board position. ]
))
(;W[co];B[bp];W[do];B[bo];W[cr];B[dn];W[bm];B[bn];W[dj]LB[cr:A][dr:B][co:C][bp:D]
C[Comparing with the game sequence, the big difference is the stone at A which was played at B in the game. A is the better move for surrounding territory, and also puts some extra pressure on the Black group. The other main difference is that White has played the C-D exchange, which has it's pros and cons. ]
))
(;W[dj];B[fp];W[fo];B[eo];W[ep];B[en];W[gp];B[fq];W[gq];B[er];W[gr];B[cp]
;W[dq];B[cq];W[dr];B[gm]
C[In this case the Master-Zero joseki works well for Black, with Black's strong position ready to attack White on the left side. ]
))

