-er bbb bbe bbf bbr bbs bbt be- beb bee bef ber bes bet bfb bfe bff bfr bfs bft brb bre brf brr brs brt bsb bse bsf bsr bss bst btb bte btf btr bts btt ebb ebe ebf ebr ebs ebt eeb eee eef eer ees eet ef- efb efe eff efr efs eft erb ere erf err ers ert es- esb ese esf esr ess est etb ete etf etr ets ett fbb fbe fbf fbr fbs fbt feb fee fef fer fes fet ffe fff ffr ffs fft frb fre frf frr frs frt fsb fse fsf fsr fss fst ftb fte ftf ftr fts ftt rbb rbe rbf rbr rbs rbt re- reb ree ref rer res ret rfb rfe rff rfr rfs rft rrb rrf rrr rrs rrt rsb rse rsf rsr rss rst rtb rte rtf rtr rts rtt sbb sbe sbf sbr sbs sbt se- seb see sef ser ses set sfb sfe sff sfr sfs sft sr- srb sre srf srr srs srt ss- ssb sse ssf ssr sss sst stb ste stf str sts stt tbb tbe tbf tbr tbs tbt te- teb tee tef ter tes tet tfb tfe tff tfr tfs tft trb tre trf trr trs trt tsb tse tsf tsr tss tst ttb tte ttf ttr tts ttt

bbbb bbbs bbeb bbet bebb bebe beeb beef beer bees beet befe beff beft bere berr bers bert bes- bese bess best bete bets bett bffs bfsr bfts bftt breb bree bref brer bres bret brrr brrs brsb brsr brst bseb bsee bser bses bset bsff bsfs bsse bsts btrt btss bttb ebbr ebbs eber ebes eeee eees eefe eers eese eete eets efbr efes efet effs eft- efts erbb erbe ereb erer eres eret erfs erft erre errs erse erst erts esbs esee eser eses eset esfs esse esst este estr ests etbr etee eter etes etfb etfe etre ette fbrs febs feeb feer fees feet fefe feff ferb fere ferr fers fert fese fess fest fete fetr fets fett ffee ffff ffrr ffss fftf free fres fret frsb frst fssf fter ftrs ftse ftsr rbbb rbbr rbbs rbss rbst rebb rebe rebs reeb reef rees reet refe reff refr refs reft rere rers rert rese ress rest rete retr rets rett rfef rrrr rsee rsre rsts rtbf rtee rtes rtfb rtss rtts sbbs sbef sber sbse sbst se-e se-f se-s se-t sebe sebs sebt seeb seef seer sees seet seff seft serb sere serf serr sers sert sese sess sest set- sete setf sets sett sfer sfss sfts sreb sres srtr ssbr ssee sses sset ssrs sssb sssf ssss sstb ssts stbs stee stef ster stes stet stre strs stsf stss sttr tbbs tbrb tbst teef teer tees teet teff teft ter- tere terf terr ters tese tess test tete tetr tets tett tfeb tfrs tfss tre- tree tref tres tret trfr trst trte trtr tses tset tsse tssf tssr tsst tsts ttbb tter ttff ttss tttt

-tree bbbee bbser be-er beber bebes beebe beebs beefs beeft beers beest beete beets beffe berbe beres beret berre berse berte berts besee beset besse beste bests betee beter betes betre betrs bett- bette betts breef breer brees breet brere brers brese bress brest brets brett brrrr btr-t btrfs ebber ebbet ebers ebert eeeee ef-ts efere efetf effer effet effts efter erbbe erber erebs erere erest erets erres erses erste ersts erte erter ertes esere esref esser esses essse estee ester estes estet estre etest etete etree etres etter ettes febre feebs feere feers feese feets feres feret ferr- ferre ferse ferte feser fesse fest- feste fests feter fetes fette freer frees freet frere frese fress frest frets frett ftest ftrtt rebbe reber rebet rebts reefe reefs reeft reere reese reest refer refet reffe refts rere- reree reres reret resee reses reset resse reste restr rests retee reter retes rette retts rsssf sebbe sebes sebet seebe seere seers seese seest seete sefer sefes seffe sefte serbs seref serer seres seret serfe serff serfs serre serse serss sert- serte serts seser seses sesse seste setee seter setse setsf sette setts sssrb sssss steer stees steet steff stere sterr sters stert stete stets strbe streb stree stret strrs tbtbt teber tebet teebs teers teese teest teets tefe teffs teres teret terre terrs terse tert- tesse teste tests teter tetes tetr- tette treer trees treet trefe treff trefs trere tres- trese tress trest trete trets trett tsebe tsere tsets ttest ttttt

b-tree bbbbbb bbsers beebee beebes beefer beerse beerst beeste beeter beffes befree befret berbee berber berbes bereet bereft berere berest berets berrer berres berret bersee berset bertes bertre besbes besbre besert besets besser besses besset bester betere betete bettee better bettes brebes breefe breere breese breest breres bresse breste brests brette bretts bs-tbs ebbers ebbert ebbest ebbets eberts eebree effere effete efreet efter- efters erbree eretes errest errett erster essebt essert essess esssse estees esters estree estres estter esttes f-test febres feeres feeses ferber ferfer ferrer ferres ferret fertee ferter fesere fesser fesses fester fetter fettes freers freese freest frefre freres fresse fresst frette fretts fterer fterre r-tree rebbes rebets reefer reeffe reeser reeses reests refeet refeff refers refert refete refret refter rerees resees resets rester restes restte reteer retees reteet retere retest retree retret retter sebete sebree sebseb see-er seesee serefe serere serers serest serre- serres serret sesser sesses sester sestet sestre setees seters setfee settee setter sssfrs steber steere steers stere- sterer steres sterre sterte street stress strete t-test t-tree tbtest teebee teerts teests teetee teeter terese terete terets terrer terres terret terser terset terter tertre tesser tesses testee tester testes tetete tetter trebes treete treets trefet trefte tresse tretee tretes trette tsetse ttests

b-trees bbbbbbb be-free beefers beetree berbere berbers berefet beretts berrett bertree bestbet besteer bestest betrese betrest betters breeses bresser brettes efreets ersters es-tset esterre estrees estreet estrete ferebee ferrere ferrers ferrest ferrets festers fetters freebee freeest freeset freeter freetts fresses fretter rebetes reefers reefest