-er b-u bbb bbc bbd bbe bbn bbr bbu bcb bcc bcd bce bcn bcr bcu bdb bdc bdd bde bdr bdu be- beb bec bed bee ben ber beu bnb bnc bnd bne bnn bnr bnu brb brd bre brn brr bru bub buc bud bue bun bur buu c-- cbb cbc cbd cbe cbn cbr cbu ccb ccc ccd cce ccn ccr ccu cdb cdc cdd cde cdn cdr cdu ce- ceb cec ced cee cen cer ceu cn- cnb cnc cnd cne cnn cnr cnu crb crc crd cre crn crr cru cub cuc cud cue cun cur cuu dbb dbc dbd dbe dbn dbr dbu dcb dcc dcd dce dcn dcr dcu ddb ddc ddd dde ddn ddr ddu de- deb dec ded dee den der deu dnb dnc dnd dne dnn dnr drb drc drd dre drn drr dru dub duc dud due dun dur ebb ebc ebd ebe ebn ebr ebu ec- ecb ecc ecd ece ecn ecr ecu ed- edb edc edd ede edn edr edu eeb eec eed eee een eer en- enb enc end ene enn enr enu erb erc erd ere ern err eru eu- eub euc eud eue eun eur nbb nbc nbd nbe nbn nbr nbu ncb ncc ncd nce ncn ncr ncu ndb ndc ndd nde ndn ndr ndu ne- neb nec ned nee nen ner neu nnb nnc nne nnn nnu nrb nrc nrd nre nrn nrr nru nub nuc nud nue nun nur nuu rbb rbc rbd rbe rbn rbr rbu rcb rcc rcd rce rcn rcr rcu rdb rdc rdd rde rdn rdr rdu re- reb rec red ree ren rer reu rnb rnc rnd rnn rnr rnu rrb rrc rrd rrn rrr rru rub ruc rud rue run rur ruu ubb ubc ube ubn ubr ubu ucb ucc ucd uce ucn ucr ucu udb udc udd ude udn udr udu ueb uec ued uee uen uer un- unb unc und une unn unr unu ur- urb urc urd ure urn urr uru uuc uue uun uur uuu