a-a a-b a-c aaa aab aac aad aah aan aao aar ab- aba abb abc abd abh abn abo abr ac- aca acb acc acd ach acn aco acr ad- ada adb adc add adh adn ado adr aha ahb ahc ahd ahh ahn aho ahr an- ana anb anc and anh ann ano anr aoa aob aoc aod aoh aon aoo aor ar- ara arb arc ard arh arn aro arr baa bab bac bad bah ban bao bar bba bbb bbc bbd bbh bbn bbo bbr bca bcb bcc bcd bch bcn bco bcr bda bdb bdc bdd bdh bdo bdr bha bhb bhc bhd bhh bho bhr bna bnb bnc bnd bnn bno bnr boa bob boc bod boh bon boo bor bra brb brd brh brn bro brr c-- caa cab cac cad cah can cao car cba cbb cbc cbd cbh cbn cbo cbr cca ccb ccc ccd cch ccn cco ccr cda cdb cdc cdd cdh cdn cdo cdr ch- cha chb chc chd chh chn cho chr cn- cna cnb cnc cnd cnh cnn cno cnr co- coa cob coc cod coh con coo cor cra crb crc crd crh crn cro crr daa dab dac dad dah dan dao dar dba dbb dbc dbd dbh dbn dbo dbr dca dcb dcc dcd dcn dco dcr dda ddb ddc ddd ddh ddn ddo ddr dh- dha dhb dhc dhd dhh dho dhr dna dnb dnc dnd dnh dnn dno dnr doa dob doc dod doh don doo dor dra drb drc drd drn dro drr haa hab hac had hah han hao har hba hbb hbc hbd hbh hbn hbo hbr hca hcb hcc hcd hch hcn hco hcr hda hdb hdc hdd hdh hdn hdo hdr hha hhb hhc hhd hhh hhn hho hhr hna hnb hnc hnd hnh hnn hno hoa hob hoc hod hoh hon hoo hor hr- hra hrb hrc hrd hrh hrn hro hrr naa nab nac nad nah nan nao nar nba nbb nbc nbd nbn nbo nbr nca ncb ncc ncd nch ncn nco ncr nda ndb ndc ndd ndh ndn ndo ndr nha nhb nhc nhd nhh nhn nhr nna nnb nnc nnh nnn nno no- noa nob noc nod noh non noo nor nra nrb nrc nrd nrn nro nrr oaa oab oac oad oah oan oao oar ob- oba obb obc obd obh obn obo obr oc- oca ocb occ ocd och ocn oco ocr oda odb odc odd odh odn odo odr oha ohc ohd ohh ohn oho ohr on- ona onb onc ond onh onn ono onr oo- ooa oob ooc ood ooh oon ooo oor or- ora orb orc ord orh orn oro orr ra- raa rab rac rad rah ran rao rar rba rbb rbc rbd rbh rbn rbo rbr rca rcb rcc rcd rch rcn rco rcr rda rdb rdc rdd rdh rdn rdo rdr rh- rha rhb rhc rhd rhh rhn rho rhr rna rnb rnc rnd rnh rnn rno rnr roa rob roc rod roh ron roo ror rra rrb rrc rrd rrh rrn rrr