-er b-p bbb bbe bbi bbp bbr bbt be- beb bee bei bep ber bet bez bi- bib bie bii bip bir bit biz bpb bpe bpi bpp bpr bpt brb bre bri brp brr brt brz btb bte bti btp btr btt btz bze bzp bzr bzz ebb ebe ebi ebp ebr ebt eeb eee eep eer eet eib eie eii eip eir eit ep- epb epe epi epp epr ept epz erb ere eri erp err ert erz etb ete eti etp etr ett etz eze ezr ezz ibb ibe ibi ibp ibr ibt ibz ie- iee iei iep ier iet iib iie iii iip iir iit ipb ipe ipi ipp ipr ipt ir- irb ire iri irp irr irt itb ite iti itp itt itz ize izi izz p-p pbb pbe pbi pbp pbr pbt pbz peb pee pei pep per pet pez pib pie pii pip pir pit piz ppb ppe ppi ppp ppr ppt ppz prb pre pri prp prr prt prz pt- ptb pte pti ptp ptr ptt ptz pzp pzt rbb rbe rbi rbp rbr rbt re- reb ree rei rep rer ret rez rib rie rii rip rir rit riz rpb rpe rpi rpp rpr rpt rpz rrb rri rrp rrr rrt rtb rte rti rtp rtr rtt rtz rzb rze tbb tbe tbi tbp tbr tbt tbz te- teb tee tei tep ter tet tez tib tie tii tip tir tit tiz tpb tpe tpi tpp tpr tpt tpz trb tre tri trp trr trt trz ttb tte tti ttp ttr ttt tze zbb zbr zbt zeb zee zep zer zet zez zib zie zip zir zit ziz zpe zpi zpp zpr zpt zrp zte ztr zzr zzt zzz

bbbb bbeb bbet bbpr bebb bebe bebi beeb beep beer beet beir beit bere beri berr bert bete beti bett betz beze bezi bibb bibe bibi bieb bier biet bipp birb bire biri birr birt bite bitt bitz bize bizz bpti breb bree brei brep brer bret brez brie brit briz brrr btbp btie btrt bttb bzer bzie bzip bzzt bzzz ebbr eber ebit eeee eete eeze eiei eier eipr eire eitb eiti eitr epee eper epi- epie epip epit eppp eprb eprp epte erbb erbe ereb erei erer eret erez erie erit eriz erpe erre ertz erzi etbr etee eter etre ette etti ezer ezri i-be ibet ibie ibri ibtb ieet ieie iere ieri iett iiie iiii iiit iitr iitt iper ipet ipie ippr ipri irbe irbp iree irer iri- irie irip irpe irre irri irte irti irtp itbe itep iter itet itie itri izet izze peep peer peet peip peir peit pepe pepi per- pere peri perp perr pert pete peti petr pett petz peze pibb pibi piep pier piet piip pipe pipi pipp pire piri pirr pite piti pitr pitt pitz pize pper ppib ppie pppp pptt pre- preb pree prep pret prez pri- prie prii prri prti prtp prtr pter rbbb rbbr rebb rebe reeb reep reet reii reir reit reiz repe repi repp repr rept rere reri rert rete reti retr rett retz reze rezi rib- ribe riep rier riet riez ripe ripi ripp ripr ript rire riri rite riti ritt ritz rize rizi rizz rpet rpii rrrr rtee rtei rttp rzip tbit tbrb tbtp teer teet teez teie teip teir tepe tepi tepp ter- tere teri terp terr tete teti tetr tett tetz tezz tibi tie- tiee tiei tiep tier tiet tiit tip- tipe tipi tipp tipt tirb tire tiri tirr tite titi titp titt titz tizi tizz tper tpir tppp tppr tpte tptp tptr tre- tree trei tret trez tri- trib trie trip trit triz trpe trpp trte trtr ttbb tter tttt tzzt zber zebe zeep zeir zeit zepp zeri zert zete zeze ziip zipp ziri zirp ziti zizi zizz zrtp zrze zzzz

-tree bbbee be-er beber bebti beebe beepi beeri beete beez beibi beier beire beite beitz beizi beppe berbe berei beret berie berit beriz berre berri berte berti berze betee beter betie betre bett- bette betti bezer bibbe biber bibie bibri biebe biere bieri biert bieti bipib birie biter bitez bitit bitte bitti bitzi bizet bizzi breer breet breit breiz brere brett bretz breze brezi bribe brier brite britt britz brize brizz brrrr btr-t bzeit bzzzt ebber ebbet ebbie ebert ebibe eeeee eepee eerie eetti eipri eirie eiter eitri eizie eppie epptb erbbe erber erept erere eretz erier erite erte erter etete etite etree etter ettie i-bet ibert ibeti iebet ieiri iepe ieper ierei iette iezer iiiee iiiii iitti ipeti ipiti ippee ippei irbit irete irite irrep irrit itbit itete itezi itire itrip itter ittre ittti itzer izier izzet p-rep pebi- pebie pebre peere peeri peert peete peetz peire peirt peitz peize pepee peppe peppi pept- perer peret perez peri- perie perit perre perri perte perti petbe peter petie petit petr- petre petri pette petti pezet pezzi piere pieri piert pierz pieze piibe piiri piper pipet pipit pippi pipri pirie pirre pirri piter pitie pitip pitre pitri pitti pitze pizze pizzi preez preie prete preti pretz preze prezi prier priez priit prite priti pritt prize pter- ptere pteri ptprb ptpre ptprr ptprt rebbe reber rebet rebit reepe reere reeti reetz reeze reitz repet repit reppe reprt rere- reree reret rerez rerip rerir retee reter retie retip rette rezip ribbi riber ribet ribie rieti rietz riper ripit rippe ririe rittz ritzi rizzi rripe tbeti tbtbt teber tebet tebi- teepe teize tepee tepet tepit teret terre terri tert- terzi teter tetr- tetri tette tezie tezir ti-ti tibbi tiber tibet tieit tiere tieri tierp tierz tietz tiper tipet tipit tippi tiree tirer tiret tirit tiriz titer titii titre titte titti tizer tizri treer treet treib treie treip treit trepp trept trere treri trete trett tribe trieb triei trier triet triip tripe tripi tripp tript trit- trite tritt ttttt tzere z-ter zebi- zebre zeitz zerbe zerit zerre zerti zetti zibet zibib ziezi zipit zippe zippr zitte zizit zizzi zrbtt zzzzz

b-tree bbbbbb bebite beebee beeper beerze beeter