-er bbb bbe bbr bbt bbx be- beb bee ber bet bex brb bre brr brt brx btb bte btr btt btx bxb bxx ebb ebe ebr ebt ebx eeb eee eer eet eex erb ere err ert etb ete etr ett etx ex- exe exr ext exx rbb rbe rbr rbt rbx re- reb ree rer ret rex rrb rrr rrt rtb rte rtr rtt rtx rxr t-x tbb tbe tbr tbt te- teb tee ter tet tex trb tre trr trt trx ttb tte ttr ttt ttx txe txt xbe xbr xbx xee xer xet xex xrt xrx xtr xtx xxx

bbbb bbeb bbet bebb bebe beeb beer beet bere berr bert bete bett breb bree brer bret brex brrr btex btrt bttb ebbr eber eeee eete eext er-x erbb erbe ereb erer eret erre etbr etee eter etre ette exer exrx exte extr rbbb rbbr rebb rebe reeb reet rere rert rete retr rett rexx rrrr rtee rtex tbrb teer teet ter- tere terr tete tetr tett tetx text tre- tree tret trex trte trtr ttbb tter tttt txtr xbee xeer xer- xert xexe xxxx

-tree bbbee be-er beber beebe beete berbe beret berre berte betee beter betre bett- bette bre-x breer breet brere brett bretx brrrr btr-t ebber ebbet ebert eeeee erbbe erber erere erte erter etete etext etree etter exert exter extre rebbe reber rebet reere rere- reree reret retee reter retex rette rexer rtext t-rex tbtbt teber tebet teret terex terre tert- teter tetex tetr- tette texte treer treet trere trete trett ttttt xbxrx xerte xetex xexex xtext xtree

b-tree bbbbbb beebee beeter berbee berber bereet berere berrer berret bertre betere betete bettee better breere brette e-text ebbert eebree erbree errett exeter r-tree reteer reteet retere retree retret retter t-tree teebee teetee teeter terete terrer terret terrex terter tertre tetete tetter texter treete tretee trette x-tree xerert

bbbbbbb beetree berbere berrett bertree bx-tree reexert reteere reterre retrete rettert terere terreer terrere tettete treetee trettre xxxxxxx

bbbbbbbb bebetter berebere betterer etbetter

beebeebee exerttrex tebe-tebe

betterbeer

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