-er b-u bbb bbc bbe bbf bbk bbr bbt bbu bcb bcc bce bcf bck bcr bct bcu be- beb bec bee bef bek ber bet beu bfb bfc bfe bff bfr bft bfu bkb bkc bke bkf bkk bkr bkt brb bre brf brk brr brt bru btb btc bte btf btk btr btt btu bub buc bue buf buk bur but buu c-- cbb cbc cbe cbf cbk cbr cbt cbu ccb ccc cce ccf cck ccr cct ccu ce- ceb cec cee cef cek cer cet ceu cfb cfc cfe cff cfk cfr cft cfu ckb ckc ckt crb crc cre crf crk crr crt cru ctb ctc cte ctf ctk ctr ctt ctu cub cuc cue cuf cuk cur cut cuu ebb ebc ebe ebf ebk ebr ebt ebu ec- ecb ecc ece ecf eck ecr ect ecu eeb eec eee eef eek eer eet ef- efb efc efe eff efr eft ekb ekc eke ekf ekr ekt eku erb erc ere erf erk err ert eru etb etc ete etf etk etr ett etu eu- eub euc eue euf eur eut fbb fbc fbe fbf fbk fbr fbt fbu fcb fcc fce fcf fck fcr fct fcu feb fec fee fef fek fer fet feu ffc ffe fff ffk ffr fft ffu fkb fkc fkf fkk fkt frb frc fre frf frk frr frt fru ftb ftc fte ftf ftk ftr ftt ftu fub fue fuf fuk fur fut fuu k-t kbb kbc kbe kbf kbk kbr kbu kcb kcc kce kck kcr kct kcu ke- keb kec kee kef kek ker ket kfc kff kfu kkb kkc kke kkk kkr kkt kku krc krf krk krr krt kru ktb ktc kte ktf ktk ktr ktt ktu kub kuc kue kuk kur kut kuu rbb rbc rbe rbf rbk rbr rbt rbu rcb rcc rce rcf rcr rct rcu re- reb rec ree ref rek rer ret reu rfb rfc rfe rff rfk rfr rft rfu rkb rkc rke rkf rkk rkt rku rrb rrc rrf rrk rrr rrt rru rtb rtc rte rtf rtk rtr rtt rtu rub ruc rue ruf ruk rur rut ruu tbb tbc tbe tbf tbk tbr tbt tbu tcb tcc tce tcf tck tcr tct tcu te- teb tec tee tef tek ter tet teu tfb tfc tfe tff tfk tfr tft tfu tkb tkc tke tkk tkr tkt trb trc tre trf trk trr trt tru ttb ttc tte ttf ttk ttr ttt ttu tub tuc tue tuf tuk tur tut tuu ubb ubc ube ubf ubk ubr ubt ubu ucb ucc uce ucf uck ucr uct ucu ueb uec uee uef uer uet ufc ufe uff ufr uft ufu ukb ukc uke ukf ukk ukr uku ur- urb urc ure urf urk urr urt uru utb utc ute utf utk utr utt utu uuc uue uur uut uuu