a-a a-b a-c aaa aab aac aad aam aan aao aar ab- aba abb abc abd abm abn abo abr ac- aca acb acc acd acm acn aco acr ad- ada adb adc add adm adn ado adr ama amb amc amd amm amn amo amr an- ana anb anc and anm ann ano anr aoa aob aoc aod aom aon aoo aor ar- ara arb arc ard arm arn aro arr baa bab bac bad bam ban bao bar bba bbb bbc bbd bbm bbn bbo bbr bca bcb bcc bcd bcm bcn bco bcr bda bdb bdc bdd bdm bdo bdr bma bmb bmc bmd bmm bmn bmo bmr bna bnb bnc bnd bnn bno bnr boa bob boc bod bom bon boo bor bra brb brd brm brn bro brr c-- caa cab cac cad cam can cao car cba cbb cbc cbd cbm cbn cbo cbr cca ccb ccc ccd ccm ccn cco ccr cda cdb cdc cdd cdm cdn cdo cdr cma cmb cmc cmd cmm cmn cmo cmr cn- cna cnb cnc cnd cnm cnn cno cnr co- coa cob coc cod com con coo cor cra crb crc crd crm crn cro crr daa dab dac dad dam dan dao dar dba dbb dbc dbd dbm dbn dbo dbr dca dcb dcc dcd dcm dcn dco dcr dda ddb ddc ddd ddm ddn ddo ddr dma dmb dmc dmd dmm dmn dmo dmr dna dnb dnc dnd dnm dnn dno dnr doa dob doc dod dom don doo dor dra drb drc drd drm drn dro drr m-o m-r maa mab mac mad mam man mao mar mba mbb mbc mbd mbm mbo mbr mc- mca mcb mcc mcd mcm mcn mco mcr mda mdb mdc mdd mdm mdn mdo mdr mma mmb mmc mmd mmm mmn mmo mmr mna mnb mnc mnm mnn mno mnr moa mob moc mod mom mon moo mor mra mrb mrc mrd mrm mrn mro mrr naa nab nac nad nam nan nao nar nba nbb nbc nbd nbm nbn nbo nbr nca ncb ncc ncd ncm ncn nco ncr nda ndb ndc ndd ndm ndn ndo ndr nma nmb nmc nmd nmm nmn nmo nmr nna nnb nnc nnm nnn nno no- noa nob noc nod nom non noo nor nra nrb nrc nrd nrm nrn nro nrr oaa oab oac oad oam oan oao oar ob- oba obb obc obd obm obn obo obr oc- oca ocb occ ocd ocm ocn oco ocr oda odb odc odd odm odn odo odr om- oma omb omc omd omm omn omo omr on- ona onb onc ond onn ono onr oo- ooa oob ooc ood oom oon ooo oor or- ora orb orc ord orm orn oro orr ra- raa rab rac rad ram ran rao rar rba rbb rbc rbd rbm rbn rbo rbr rca rcb rcc rcd rcm rcn rco rcr rda rdb rdc rdd rdm rdn rdo rdr rma rmb rmc rmd rmm rmn rmo rmr rna rnb rnc rnd rnm rnn rno rnr roa rob roc rod rom ron roo ror rra rrb rrc rrd rrm rrn rrr