-er eee eek eer eet eke ekr ekt ere erk err ert erz ete etk etr ett etz eze ezr ezz k-t k-z ke- kee kek ker ket kez kke kkk kkr kkt krk krr krt kte ktk ktr ktt re- ree rek rer ret rez rke rkk rkt rkz rrk rrr rrt rte rtk rtr rtt rtz rze te- tee tek ter tet tez tke tkk tkr tkt tkz tre trk trr trt trz tte ttk ttr ttt tze zee zek zer zet zez zte ztr zzr zzt zzz

eeee eeke eete eeze ekek eker eket erer eret erez erke erre ertz etee eter etre ette ezek ezer keek keer keet keke ker- kere kerk kerr kert kerz ket- kete ketk ketr kett keze kezr kezz kkez kkkk kkre kkrk kkrr kkrt kkrz kktk kktz kkzz kree krek kret krez krke krkk krkr krkz krre krrk krrr krrt krrz krtk krtr krtz krze krzk krzr krzz ktee ktek ktez ktke ktkk ktkr ktkt ktkz ktre ktrk ktrr ktrt ktrz kttk kttr kttt kttz ktzk ktzr ktzt ktzz kzee kzer kzke kzkr kzkz kzrk kzrr kzrz kztk kzzk kzzr kzzt kzzz reek reet reke rekt rere rert rete retr rett retz reze rrrr rtee teek teer teet teez teke ter- tere terk terr tete tetr tett tetz tezz tre- tree trek tret trez trte trtr tter tttt tzzt zeek zeke zekr zerk zert zete zeze zrze zzzz

-tree eeeee ekker erere eretz erte erter eteke etete etree etrek etter keere kerek keret kerre ketek keter kette kreek kreke krete kretz reere reetz reeze rekke rere- reree reret rerez retee reter rette rezek rt-rk teket tekke terek teret terre tert- teter tetr- tette tkzee treer treet trere trete trett trzek ttttt tzere z-ter zerre zzzzz

errett etrez k-tree keeker kerker kertee ketter kreker krekez kretek r-tree reeker reteer reteet retere retree retret retter t-tree teetee teeter terete terrer terret terter tertre terzet tetete tetter treete treker tretee trette tzetze zekeze zertz zezere

ekekete kee-kee kreeker reteere reterre retrete rettert terere terreer terrere tettete tezkere treetee trekker trettre

erezee ketterer teketeke trezerer

keek-keek