(;GM[1]FF[4]SZ[19]AP[SmartGo:3.1.7]CA[shift_jis]
GN[36]
PW[AlphaGo]
PB[AlphaGo]
EV[AlphaGo selfplay]RO[36]
KM[7.5]
RE[B+R]
RU[Chinese]MU[1];B[pd];W[dd];B[pp];W[cp];B[eq];W[dn];B[cc];W[dc];B[cd];W[cf]
;B[ce];W[de];B[bf];W[nq];B[qn]
(;W[cb]
C[Up to Black 15, this was identical to game 19 of this set, in which White approached the UR corner (see var). ]
;B[bb]
(;W[bg]
C[With White's double hane, cutting on the second line was also a popular joseki (see var). ]
;B[db]
(;W[eb]
C[While covering at 20 used to be an only move, computer programs have recently started to suggest a connection on the fourth line (see var). ]
;B[cg];W[df];B[bh];W[dg];B[ag];W[qc];B[pc];W[qd];B[qf];W[qe];B[pe];W[rf]
;B[qb];W[rb];B[rg];W[pb];B[re]
C[AG shows us yet another version of this joseki that is feasible and can be seen sometimes in human play. Similarly to the UL corner joseki, Black had the option to connect on the fourth line with this move. ]
;W[pf];B[qg];W[qa];B[of]
C[Naturally, it is required that the ladder favors Black. ];W[hq];B[rd];W[rc]
(;B[mj]
C[This has become the standard move for Black to keep the ladder. The idea seems to be that Black wants to play as far as possible from the wall, but close enough to be able to fight strongly when White plays a ladder breaking move inside the moyo. An example of Black playing too far away is shown as a variation. ]
;W[mh];B[ni]
C[Black 47 is the strongest move, but does not actually prevent White from escaping the ladder, as we shall see. ]
;W[pg];B[ph];W[og];B[ng];W[oh];B[nh];W[oi]
(;B[pj]
C[Black goes for the squeeze. Continuing to attack with ataris would have been bad (see var). ]
;W[oj];B[ok];W[oe];B[nf];W[oc];B[pi];W[od]LB[mj:A][mh:B][nk:C]
C[White escaped from the ladder, and Black squeezed to get an even result. While Black's stone at A looks like an awkward shape, it is probably more useful than the White stone at B. If White later attacks at C, Black's stone at A will join the fight. ]
;B[oq];W[np];B[lq]
(;W[nm]LB[nk:A]
C[White seems to be looking to attack at A next when it plays 66. However, this was not the expected move, and I was happy to see that Leela also thinks that the diagonal jump was normal (see var)]
;B[lo];W[lm];B[ip];W[pm]
C[White is aiming to cut on the fourth line. ]
(;B[pe]
C[Black protects the cutting point and has a small advantage. Allowing the cut would lead to an even fight (see var). ]
;W[pd];B[nj];W[pe];B[pk];W[hp];B[ho];W[iq];B[io];W[go];B[oo]
C[Black takes away White's eye space while threatening to capture two stones. ]
;W[pn];B[po]
(;W[lk]TR[np:nq]
C[Saving the two marked stones looks dangerous, and White will be in a tight spot even if Black allows the group to live (see var). ]
;B[mn];W[qq];B[or];W[ro];B[rp]LB[qp:A]
C[White can live in the corner by playing at A, but the center is more important. ]
;W[mm];B[cq];W[bq];B[br]
C[Black's hane is the tesuji to make a living shape in the corner. ];W[kp]
;B[lp]
(;W[dq]
C[White allows the Black group to make eyes. The more aggressive move would be to cut on the second line (see var). ]
;B[cr];W[dp];B[dr];W[ko];B[kq];W[kn];B[gn];W[fp];B[jq];W[ki];B[jf];W[rn]
;B[qp]LB[rn:A][qp:B][ql:C]
C[The exchange of A for B gave White a potential eye. White's best move on the side is C. ]
(;W[nn]
C[Does White need this bamboo joint? Well, there is a little problem if White plays away (see var). ]
;B[on];W[no];B[nr];W[om];B[jm];W[jk];B[jd];W[fn];B[gm];W[ql]LB[rk:A]
C[White makes an eye on the side, and will get a living shape next with White A.]
(;B[hc]
C[Having reduced White potential on the upper side, Black has established a small lead. A variation is added to demonstrate that Black gains little from the double peep in the center. ]
;W[gk]LB[jp:A]
C[White tries to force Black to defend at A. ];B[fm]
C[Since A is a worthless point, it is reasonable that Black tries to avoid playing there. ]
;W[em];B[el];W[dl];B[fk];W[ek];B[fl];W[fj];B[gj];W[ej];B[hk];W[gi];B[hj]
;W[il]LB[hn:A]
C[White's kosumi continues to pressure the Black group, taking away Black's eye space and creating a cut at A. ]
;B[hi];W[hl];B[gl];W[ih];B[hh];W[ig];B[im];W[ie];B[if];W[hg];B[jj];W[kk]
;B[ji];W[kg];B[kj];W[lj];B[li];W[kh];B[mk]LB[nk:A][km:B][ll:C]
C[Now it becomes apparent that the struggle in the center was mostly for Black to force here and forestall White's cut at A. Black now threatens to force with B and wedge at C to cut White off. ]
;W[rk];B[rj];W[km];B[jl];W[ik];B[jp]
C[Finally, Black is forced to connect. ];W[kc]LB[qo:A][mi:B]
C[If Black connects at A, White can cut at B. ];B[ca];W[bp]
(;B[fq];W[qo]LB[qo:A][mg:B][kg:C]
C[White A indirectly attacks Black's group on the upper side. Now Black B is no longer forcing, and thus White's group at C is stronger than it was before. ]
;B[jc];W[kd];B[ge]
C[Black A was a hard move to find, but it seems to be highly effective. Black can make good shape with B next. ]
LB[ge:A][fc:B];W[ci];B[bi];W[je];B[kb]LB[ge:A][kb:B][ke:C]
C[Black A and B combine to make Black C a powerful threat. ];W[he]
(;B[fc]
C[Black peeps first. It is not wise to extend on the second line yet (see var). ]
;W[lb];B[ec];W[bj];B[ch];W[gd];B[gc];W[jb];B[ib];W[ka];B[bk];W[cj];B[aj]
;W[gr];B[fr];W[hd];B[dh];W[fg];B[ic];W[bl];B[ck];W[dk];B[cl];W[cm];B[ak]
;W[sp];B[sq];W[so];B[rq];W[ep];B[qk];W[rl];B[me];W[ar];B[es];W[le];B[gh]
;W[hs];B[fs]
(;W[fd]
C[This is where I tried a different endgame for White. The variation ends with Black winning by half a point. ]
;B[lf];W[mg];B[mf];W[kf];B[bm];W[bn];B[gg];W[gf];B[fi];W[dj];B[md];W[jr]
;B[kr];W[am];B[sj];W[ia];B[ha];W[ja];B[ld];W[ai];B[ah];W[al];B[ai];W[ga]
;B[hb];W[fb];B[gb];W[nc];B[ke];W[ed];B[fa];W[le];B[js];W[ir];B[ke];W[hm]
;B[hn];W[le];B[ff];W[fe];B[ke];W[lc];B[mc];W[mb];B[jh];W[jg];B[lg];W[lh]
;B[gq];W[gp];B[mi];W[sc];B[ii];W[le];B[sf];W[ke];B[eg];W[ef];B[eh];W[mq]
;B[mr];W[sd];B[se];W[kl];B[ml];W[bs];B[cs];W[gs];B[sk];W[sl];B[ks];W[is]
;B[nl];W[ol];B[as];W[jn];B[in];W[bs];B[fh];W[aq];B[as];W[pl];B[op];W[bs]
;B[ff];W[mo];B[ln];W[ll];B[fg]
(;W[dm];B[as]
C[B+0.75 stones(B+1.5pts)
As always, AG has unusual ways to handle the final ko, but there were no game-changing mistakes. ]
)
(;W[as];B[ei]
C[B+0.75 stones (0.5pts)]))
(;W[sj];B[si];W[sk];B[ri];W[hm];B[hn];W[md];B[bm];W[bn];B[dj];W[di];B[ei]
;W[dj];B[fi];W[dm];B[fe];W[gf];B[fd];W[ff];B[lf];W[kf];B[al];W[jr];B[kr]
;W[ks];B[ls];W[js];B[jh];W[jg];B[ia];W[ne];B[mg];W[gq];B[gs];W[ir];B[ja]
;W[an];B[am];W[sd];B[sf];W[mq];B[mr];W[kb];B[mf];W[lh];B[mi];W[sc];B[se]
;W[bs];B[cs];W[gg];B[eg];W[ef];B[eh];W[aq];B[nk];W[as]LB[qm:A]
C[White must add a stone at A. Black wins by half a point.]))
(;B[lb];W[gc];B[gb];W[hd];B[ib];W[gr];B[fr];W[bj]TR[ge]
C[White gets some extra territory by cutting off the marked stone. ]))
(;B[qo];W[mi];B[fq]))
(;B[kl];W[kk];B[ll];W[mk];B[ml];W[nk];B[nl];W[rk]LB[ri:A][qo:B]
C[Black cannot afford to allow White A, so White can live with B next. ]
))
(;W[jd];B[qm];W[ql];B[om];W[qo];B[on];W[pl];B[rk]
C[Black has this move at A to connect the right side into a large territory. ]
LB[qm:A]))
(;W[cr];B[dq];W[ar];B[bp];W[bs];B[co];W[dp];B[fo];W[do];B[gn];W[gp];B[jj]
C[When Black's attack on the White group on the right is combined with the threatened Black move at A, this becomes a very difficult fight for White. ]
LB[fp:A]))
(;W[no];B[kp];W[qm];B[rn];W[mn];B[kl];W[on];B[nr];W[ml];B[cq];W[bq];B[br]
C[This was already a successful attack for Black, so Black can getr an advantage wit simply living in the corner. ]
))
(;B[pn];W[pk];B[pe];W[pd];B[nj];W[pe];B[qk];W[pl];B[nl];W[ql];B[on];W[om]
;B[rk];W[rl];B[ri];W[nn]
C[Both sides have groups in the center that are not settled, and this looks about even. ]
))
(;W[ln]LB[mo:A][lp:B]
C[The diagonal jump shown here was the normal shape, and White can answer Black A with White B to make sabaki. ]
))
(;B[oj];W[pi];B[pj];W[qi];B[ne];W[sf];B[qj];W[rh]
C[White wins the semeai, and this is bad for Black. ]))
(;B[ll];W[mj];B[oj];W[no]LB[ll:A]
C[When Black plays too far away, White can play a ladder breaking move between A and the wall, and Black's moyo loses volume so this is bad for Black.]
))
(;W[dg];B[eb];W[hq]
C[When compared with the solid connection at A, White's hanging connection at B has about the same value, and in this board position it works well with White's moyo on the left. ]
LB[df:A][dg:B]))
(;W[be];B[db];W[bc];B[ca];W[bd];B[cb];W[bg];B[df];W[cg];B[ee];W[ef];B[dg]
;W[fd];B[fc];W[fe];B[hc];W[fg]LB[ee:A]
C[This var shows a modern version of the joseki. Black A is played when Black wants to avoid White capturing the cutting stone in a ladder. ]
))
(;W[nc];B[cg];W[df];B[cb];W[qf]
C[Game 19]))

