-er b-u bbb bbc bbe bbk bbl bbr bbt bbu bcb bcc bce bck bcl bcr bct bcu be- beb bec bee bek bel ber bet beu bkb bkc bke bkk bkl bkr bkt blb blc ble blk bll blr blt blu brb bre brk brl brr brt bru btb btc bte btk btl btr btt btu bub buc bue buk bul bur but buu c-- cbb cbc cbe cbk cbl cbr cbt cbu ccb ccc cce cck ccl ccr cct ccu ce- ceb cec cee cek cel cer cet ceu ckb ckc ckt cl- clb clc cle clk cll clr clt clu crb crc cre crk crl crr crt cru ctb ctc cte ctk ctl ctr ctt ctu cub cuc cue cuk cul cur cut cuu ebb ebc ebe ebk ebl ebr ebt ebu ec- ecb ecc ece eck ecl ecr ect ecu eeb eec eee eek eel eer eet ekb ekc eke ekl ekr ekt eku elb elc ele elk ell elr elt elu erb erc ere erk erl err ert eru etb etc ete etk etl etr ett etu eu- eub euc eue eul eur eut k-t kbb kbc kbe kbk kbl kbr kbu kcb kcc kce kck kcl kcr kct kcu ke- keb kec kee kek kel ker ket kkb kkc kke kkk kkl kkr kkt kku kl- klb klc klr klt klu krc krk krl krr krt kru ktb ktc kte ktk ktl ktr ktt ktu kub kuc kue kuk kul kur kut kuu lbb lbc lbe lbk lbl lbr lbt lbu lcb lcc lce lck lcl lcr lct lcu leb lec lee lek lel ler let leu lkb lkl lkr lkt llb llc lle llk lll llr llt llu lrb lrc lrk lrr lrt lru ltb ltc lte ltk ltl ltr ltt ltu lub luc lue luk lul lur lut luu rbb rbc rbe rbk rbl rbr rbt rbu rcb rcc rce rcl rcr rct rcu re- reb rec ree rek rel rer ret reu rkb rkc rke rkk rkt rku rlc rle rll rlr rlt rlu rrb rrc rrk rrl rrr rrt rru rtb rtc rte rtk rtl rtr rtt rtu rub ruc rue ruk rur rut ruu tbb tbc tbe tbk tbl tbr tbt tbu tcb tcc tce tck tcl tcr tct tcu te- teb tec tee tek tel ter tet teu tkb tkc tke tkk tkl tkr tkt tlc tle tlk tll tlr tlt tlu trb trc tre trk trl trr trt tru ttb ttc tte ttk ttl ttr ttt ttu tub tuc tue tuk tul tur tut tuu ubb ubc ube ubk ubl ubr ubt ubu ucb ucc uce uck ucl ucr uct ucu ueb uec uee uel uer uet ukb ukc uke ukk ukl ukr uku ulb ulc ule ulk ull ulr ult ulu ur- urb urc ure urk url urr urt uru utb utc ute utk utl utr utt utu uuc uue uur uut uuu