(;GM[1]FF[4]SZ[19]AP[SmartGo:3.1.4]CA[shift_jis]
GN[32]
PW[AlphaGo]
PB[AlphaGo]
EV[AlphaGo selfplay]RO[32]
KM[7.5]
RE[W+R]
RU[Chinese]MU[1];B[pd];W[dd];B[qp];W[dp];B[fq];W[cn];B[lq];W[qc]LB[qf:A][nc:B][qj:C]
C[White's early 3-3 invasion could have been at A or B, while C has all but dissappeared from play. The 3-3 invasion has become the most popular move for White. ]
;B[qd];W[pc];B[od]
(;W[nc]
C[White 12 has always been called a mistake, until AG played it. Maybe I am behind the times but I still don't like it. I think it is better for White to slide (see var). ]
;B[nd];W[mc];B[oc];W[ob];B[nb];W[pb];B[lc];W[mb];B[md];W[lb]
C[The human analysis says that it was painful for White to play so many moves on the second line, and Black has a big wall, so Black must have an advantage. However, computer programs will say that White's score has improved compared to the start of the game. To take the side of AG, I could say that Black has already used up all of its potential to push the corner around, and Black has no forcing moves or ko threats. White has filled all of the marked liberties underneath the Black wall, making it weak in a semeai. The Black wall has no eyes. ]
TR[lb][ob][mc:nc][pc:qc];B[pk];W[qi];B[pi]
(;W[pp]
C[White is not just tossing stones about. To describe this in human terms, White has a plan to coordinate these two stones to get a good result on the right. I realize that AG does not have 'plans' in the way we do, but that is how I translate what it does into something that I think I understand. 
Living on the right on a small scale is not good enough for White here (see var). ]
;B[pq];W[ph];B[oi];W[qo];B[op];W[po];B[qq];W[rk]
C[Sliding on the second line and leaving the cut at A is a pattern we have seen before, in game 3 of this set. ]
LB[qh:A]
(;B[ql]TR[po:pp][qo]
C[Black chose to cut off the marked White stones. If Black had cut on the third line, White would have connected up to live on the right side (see var).]
;W[rl];B[rm];W[qm];B[qn];W[pm];B[ro];W[qg];B[oh];W[og];B[ng]
(;W[nf]
C[White 46 is an amazingly sharp move that makes use of White's ko threat at the marked point. Simply extending with this move is not as good (see var). ]
TR[pn];B[of];W[pf];B[pg];W[pn];B[rn];W[og];B[oe];W[pg];B[mg];W[lm]LB[nf:A][le:B][kf:C]
C[White's cutting stone at A creates a weakness in Black's wall that can be used with forcing moves at B or C. ]
(;B[rf]
C[The var shows Black's strongest attempt to attack White on the side, which is not successful (see var). ]
;W[qj];B[ok];W[rg];B[jm];W[np]LB[kp:A][lk:B]
C[White's clamp at 62 could be described as an attempt to fix White's shape, but when one considers the fact that Black's corner is already alive and Black does not neccesarily need to answer directly, this is the beginning of a dangerous fight in which Black will attempt to capture the White group. If White had simply escaped with a play at A or B, the game would have been relatively peaceful. ]
(;B[mo]
C[Black attacks strongly. Connecting on the third line would have made White happy (see var). ]
(;W[nn]
C[White maintains a connection to the center. Cutting on the third line was too dangerous (see var). ]
(;B[kl]
C[White has offered to sacrifice one stone (see var), but Black is going after the whole group. ]
;W[oq];B[lo];W[ll];B[nl];W[nr];B[mq]LB[lo:A][nl:B][mq:C]
C[Taking one vital point after another with A~C, Black is playing the strongest possible attack. ]
;W[nm]
(;B[pr]
C[Black needed the stone at 73 to prevent White from making two eyes (see var). ]
;W[lj];B[kj]
C[Black plays at 75 with the idea (if White simply extends) to force with A and wedge at B next, with the stone at 75 preventing White from cutting at C (see var for 76). ]
LB[ml:A][lk:B][kk:C]
(;W[jn]TR[ln]
C[White's attachment at 76 works to create a forcing move for White at the marked point. White 76 must be played now, and is not so effective if it comes later (see var). ]
;B[kn];W[li]
(;B[lk]
C[Black cannot cut White this time (see var). ];W[mk];B[kk];W[ml]
(;B[nh]
(;W[lg]
C[White should have played a cut in the center before White 84 (see var). ]
(;B[mj]
C[Black cannot save the cutting stone at 85, and I will call it the losing mistake. Black should have just answered with a hane (see var). ]
;W[mi]
(;B[lf]
C[Saving the one stone was not a valid option for Black (see var). ];W[nj]
C[The false eye at A will sometimes change into a real eye, when White can squeeze in connection to the cut at B. ]
LB[mj:A][mf:B];B[mn];W[mm];B[kg];W[ki];B[ji];W[jh];B[kh];W[jj];B[ii];W[km]
;B[jl];W[in]
(;B[iq]
C[Naturally I had the question, what would have happened if Black had protected in the center? (see var)]
;W[ij];B[hj];W[ik];B[il];W[hk];B[hm];W[ip]
C[White's connection at A is still relevant, as we will find later. For now, White is molesting Black in the center and on the lower side. ]
LB[lh:A];B[jp];W[hq]
(;B[ir]
C[It might seem that Black wanted to cut with this move, but that tangles up with the center (see var). ]
;W[ko];B[ln];W[kp];B[jq];W[jo];B[gm];W[go];B[hr];W[nq]LB[nq:A][lh:B]TR[kn:mn][lo:mo]
C[With the connection at A and potential to squeeze the marked Black stones, White's connection at B will now help White make eyes. ]
(;B[ol]
C[With Black 121, the intuitive move would have been to push through and give White a false eye. This would not stop White's plan to make use of Black's shortage of liberties (see var). ]
(;W[gq]
C[White already had a sequence to make eyes for the surrounded group (see var). In the game White is just continuing the attack first. ]
;B[gr];W[fp];B[eo];W[ep];B[hi];W[no];B[mr];W[hl];B[im];W[fl];B[gl];W[gk]
;B[fk];W[gj];B[el];W[ni]
(;B[hp];W[qk]LB[lh:A][kf:B]
C[I would say that White should have played at A, and if Black B the White group is already alive, so White seems to have lost a tempo here. However,  AlphaGo would probably tell me that it doesn't care, and White will win anyway. ]
;B[gp];W[en];B[fn];W[fo];B[cl];W[fj];B[pl];W[nk];B[cq];W[bl];B[bk];W[dl]
C[White settles the corner group with this cute tesuji. ]
(;B[ek]
C[Black could not cover on the fourth line (see var). ];W[ck];B[dk];W[cm]
;B[cj];W[em];B[fm];W[cl];B[di];W[gh];B[hg];W[hh];B[ih];W[ig];B[jg];W[if]
;B[hf];W[gi];B[jh];W[dg];B[eh];W[gf];B[he];W[gg];B[ge];W[eg];B[ho];W[ei]
;B[hn];W[kc];B[ie];W[er];B[dr];W[cc])
(;B[dk];W[ek];B[em];W[dm]
C[There is still a ko at A, but it should be clear that this is just bad for Black. ]
LB[hn:A]))
(;B[nk];W[lh];B[mf];W[fj];B[fm];W[hh];B[gi];W[fh];B[fi];W[ei];B[ej];W[ih]
;B[jk];W[kf]LB[lh:A][kf:B][mf:C]
C[Again White A was the final blow, with Black having to choose between B and C. This var shows yet another way for White to set up a ladder in the center. ]
))
(;W[no];B[kq];W[lh];B[mf];W[ih];B[hi];W[hh];B[gh];W[gg];B[hg];W[gi];B[gj]
;W[hl];B[im];W[fj];B[gk];W[gl];B[fk];W[fl];B[ek];W[fm]TR[ni][oj:pj][nk][qk][pl][om]
LB[lh:A][mf:B][kf:C]
C[I admit I had some fun with this var, and it is more flashy than was necessary. White finishes Black off with a threatened ladder and captures ten stones in the center. The decisive move was again White A, when Black had to choose between connecting at B (this var), and connrecting at C, in which case White would start filling the marked liberties to make eyes or connect to the side. ]
))
(;B[no];W[oo];B[kq];W[lh];B[kf];W[nk];B[ol];W[om];B[ni];W[pj];B[oj];W[qk]
;B[mf];W[pl]LB[lh:A][kf:B][mf:C]
C[As in many of the vars, White's connection at A becomes the decisive move that forces Black to choose between the connection at B which allows White to squeeze and save the group, and the connection at C instead, which would end with Black collapsing in the center. ]
))
(;B[hp];W[ho];B[io];W[hn];B[gm];W[gp];B[hr];W[ip];B[jr];W[fl]LB[hp:A]
C[Black's cut at A has not slowed White down at all, and has actually given White some extra eye shape. This var is trouble for Black.]
))
(;B[ik];W[ko];B[ln];W[jq];B[jp];W[ip];B[nq];W[or];B[mr];W[oo];B[ms];W[ns]
;B[jr];W[ir];B[kq];W[iq];B[ks];W[lh];B[kf];W[nk];B[ol];W[qk];B[pl];W[pj]
;B[oj];W[om]
C[This is the short version in which White can make eyes. With Black's connection at A, if Black had played at B to stop White from living as shown here, then White would have pushed at C and then cut at A, and Black would have trouble on the right and with two groups in the center. I will try to include the 50 move version in my YouTube video. ]
LB[kf:A][mf:B][ih:C]))
(;B[nj];W[pj];B[oj];W[ol];B[nk];W[pl];B[lf];W[qk]LB[nj:A][pj:B]
C[If Black escapes one stone at A, then White B is the correct order of moves, and Black will eventually run out of liberties. If White can make eyes or connect as shown here, White will have a clear advantage. ]
))
(;B[lf];W[nj];B[kg]LB[mj:A][mi:B][km:C]
C[This can be compared to the game, only Black has not played the exchange of A for White B, which gave White a potential eye, so this is clearly better for Black. White has the option to cut at C after the marked exchange and get into a variation similar to what I showed as a var for White 84, but in that case the marked exchange will become a terrible blunder for White, as it strengthens the Black group.]
TR[lf:lg]))
(;W[km];B[mj];W[in];B[im];W[jp];B[ln];W[jr];B[mr];W[hm];B[ik];W[dq]LB[kc:A][le:B]
C[In this variation Black has killed the White group to get almost 60 pts, but White is ok with compensation on the lower side. Later White can play the big move at A and then peep at B, with potential to squeeze the Black group on the right. ]
))
(;B[mj];W[mi];B[nj];W[pj];B[oj];W[ol];B[nk];W[nh];B[mh];W[pl]LB[mj:A][ol:B]
C[If Black cuts at A, White can live with the atari at B. This var shows Black heading into a disaster, with White squeezing while connecting to the side. ]
))
(;B[ml];W[ln];B[lk];W[km]
C[Black collapses. ]))
(;W[li];B[ml];W[ln];B[lk];W[jn];B[in];W[jo];B[im]LB[kj:A][li:B][ml:C][kn:D]
C[This var shows the plan behind Black A. The exchange of Black A for White B is a huge plus for Black when Black cuts White off with C and the following wedge. Black is threatening D and since White is short of liberties, White does not have time to attack Black on the lower side. White's group will continue to be harassed, and Black is profiting on all sides. ]
))
(;B[lk];W[pr];B[qr];W[qs];B[rs];W[ps];B[rq];W[pl];B[qk];W[ol];B[mr];W[nk]
;B[mk];W[ml];B[nj];W[mn]LB[pr:A][om:B][mm:C][os:D]
C[White A and the hanetsugi on the first line threaten a ko in the corner, after which White can make an eye at B, with a second eye at C or D. ]
))
(;B[no];W[oo];B[oq];W[lo];B[mn];W[mm];B[mp];W[lk];B[jk];W[ln];B[jo];W[mi]
C[This is a relatively peaceful variation, in which Black settles for some profit on the lower side and a continuing attack, while White will be able to escape in the center. White has a small advantage. ]
))
(;W[oq];B[no];W[oo];B[nm];W[nn];B[mn];W[mm];B[nl];W[mq];B[mp]LB[lr:A][mr:B][nr:C]
TR[nn]
C[With the marked stone in atari, White has no effective counter-attack. If White plays at A, Black B, and White C, it will be a ko, but White has no valid ko threat. ]
))
(;B[oq];W[ko];B[io];W[lp];B[kq];W[oo]
C[White is close to getting eyeshape now. Most of Black's moyo has dissappeared and Black will have a hard time trying to catch up in territory. ]
))
(;B[qj];W[rj];B[ri];W[qh];B[rf];W[pl];B[qk];W[ok];B[pj];W[si];B[sh];W[rh]
;B[sg];W[rg];B[sf];W[re]
C[This var shows Black's strongest attempt to attack White's group on the side, and demonstrates how White's stone at A has a direct connection to the life or death of White's group. This is clearly a disaster for Black. ]
LB[pf:A]))
(;W[of];B[nf];W[pn];B[rn];W[lm];B[rh];W[qh];B[re];W[rf]LB[pf:A][rg:B][pl:C][ri:D]
C[This variation is very subtly better for Black when compared to the game. While Black has no killing attack, there are various ways in which Black can squeeze the White group. Black A or B would reinforce the outside Black group while forcing White to live, or otherwise,  a Black play at Cwould threaten to play at D while threatening White on the outside. ]
))
(;B[qh];W[ri];B[qg];W[pl];B[ol];W[pm]LB[qh:A][pl:B]
C[If Black cuts at A, White will attach at B to live on the right side. This is a satisfactory result for White. ]
))
(;W[ph];B[oi];W[qk];B[ql];W[qj];B[pl];W[rg];B[oh];W[pg];B[qf];W[og];B[ng]
;W[nf];B[mg];W[rl];B[rm];W[sl];B[kc]LB[qk:A][rg:B]
C[If White attaches at A and takes the vital point at B, it will be relatively simple for White to live here. However, Black gets huge thickness on the outside, and this is a good result for Black. ]
))
(;W[nb];B[pj]LB[pj:A][pk:B]
C[Black's move on the right can be at A or B. This is about even. ]))

