-er a-a a-b a-c a-t aaa aab aac aad aae aar aat aau ab- aba abb abc abd abe abr abt abu ac- aca acb acc acd ace acr act acu ad- ada adb adc add ade adr adt adu aea aeb aec aed aee aer aet aeu ar- ara arb arc ard are arr art aru at- ata atb atc atd ate atr att atu au- aua aub auc aud aue aur aut b-u baa bab bac bad bae bar bat bau bba bbb bbc bbd bbe bbr bbt bbu bca bcb bcc bcd bce bcr bct bcu bda bdb bdc bdd bde bdr bdt bdu be- bea beb bec bed bee ber bet beu bra brb brd bre brr brt bru bta btb btc btd bte btr btt btu bua bub buc bud bue bur but buu c-- caa cab cac cad cae car cat cau cba cbb cbc cbd cbe cbr cbt cbu cca ccb ccc ccd cce ccr cct ccu cda cdb cdc cdd cde cdr cdt cdu ce- cea ceb cec ced cee cer cet ceu cra crb crc crd cre crr crt cru cta ctb ctc ctd cte ctr ctt ctu cua cub cuc cud cue cur cut cuu daa dab dac dad dae dar dat dau dba dbb dbc dbd dbe dbr dbt dbu dca dcb dcc dcd dce dcr dct dcu dda ddb ddc ddd dde ddr ddt ddu de- dea deb dec ded dee der det deu dra drb drc drd dre drr drt dru dta dtb dtc dtd dte dtr dtt dtu dua dub duc dud due dur dut eaa eab eac ead eae ear eat eau eba ebb ebc ebd ebe ebr ebt ebu ec- eca ecb ecc ecd ece ecr ect ecu ed- eda edb edc edd ede edr edt edu eea eeb eec eed eee eer eet era erb erc erd ere err ert eru eta etb etc etd ete etr ett etu eu- eua eub euc eud eue eur eut ra- raa rab rac rad rae rar rat rau rba rbb rbc rbd rbe rbr rbt rbu rca rcb rcc rcd rce rcr rct rcu rda rdb rdc rdd rde rdr rdt rdu re- rea reb rec red ree rer ret reu rra rrb rrc rrd rrr rrt rru rta rtb rtc rtd rte rtr rtt rtu rua rub ruc rud rue rur rut ruu taa tab tac tad tae tar tat tau tba tbb tbc tbd tbe tbr tbt tbu tca tcb tcc tcd tce tcr tct tcu tda tdb tdc tdd tde tdr tdt tdu te- tea teb tec ted tee ter tet teu tra trb trc trd tre trr trt tru tta ttb ttc ttd tte ttr ttt ttu tua tub tuc tud tue tur tut tuu ua- uaa uab uac uad uae uar uat uau uba ubb ubc ube ubr ubt ubu uca ucb ucc ucd uce ucr uct ucu uda udb udc udd ude udr udt udu uea ueb uec ued uee uer uet ur- ura urb urc urd ure urr urt uru uta utb utc utd ute utr utt utu uua uuc uue uur uut uuu