-er bbb bbe bbr bbt be- beb bee ber bet bez brb bre brr brt brz btb bte btr btt btz bze bzr bzz ebb ebe ebr ebt eeb eee eer eet erb ere err ert erz etb ete etr ett etz eze ezr ezz rbb rbe rbr rbt re- reb ree rer ret rez rrb rrr rrt rtb rte rtr rtt rtz rzb rze tbb tbe tbr tbt tbz te- teb tee ter tet tez trb tre trr trt trz ttb tte ttr ttt tze zbb zbr zbt zeb zee zer zet zez zte ztr zzr zzt zzz

bbbb bbeb bbet bebb bebe beeb beer beet bere berr bert bete bett betz beze breb bree brer bret brez brrr btrt bttb bzer bzzt bzzz ebbr eber eeee eete eeze erbb erbe ereb erer eret erez erre ertz etbr etee eter etre ette ezer rbbb rbbr rebb rebe reeb reet rere rert rete retr rett retz reze rrrr rtee tbrb teer teet teez ter- tere terr tete tetr tett tetz tezz tre- tree tret trez trte trtr ttbb tter tttt tzzt zber zebe zert zete zeze zrze zzzz

-tree bbbee be-er beber beebe beete beez berbe beret berre berte berze betee beter betre bett- bette bezer breer breet brere brett breze brrrr btr-t bzzzt ebber ebbet ebert eeeee erbbe erber erere eretz erte erter etete etree etter rebbe reber rebet reere reetz reeze rere- reree reret rerez retee reter rette tbtbt teber tebet teret terre tert- teter tetr- tette treer treet trere trete trett ttttt tzere z-ter zebre zerbe zerre zrbtt zzzzz

b-tree bbbbbb beebee beerze beeter beezer berbee berber bereet berere berrer berret bertre betere betete bettee better betzet breere breeze brette ebbert eebree erbree errett etrez r-tree reteer reteet retere retree retret retter t-tree teebee teetee teeter terete terrer terret terter tertre terzet tetete tetter treete tretee trette tzetze zeebee zerbet zertz zezere

bbbbbbb beetree berbere berrett bertree betbeze reteere reterre retrete rettert terere terreer terrere tettete trebez treetee trettre zbereze zerbert

bbbbbbbb bebetter berebere betterer erezee etbetter trezerer

beebeebee tebe-tebe

betterbeer

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