a-a a-b a-c aaa aab aac aad aah aak aar ab- aba abb abc abd abh abk abr ac- aca acb acc acd ach ack acr ad- ada adb adc add adh adk adr aha ahb ahc ahd ahh ahk ahr aka akb akc akd akh akk akr ar- ara arb arc ard arh ark arr baa bab bac bad bah bak bar bba bbb bbc bbd bbh bbk bbr bca bcb bcc bcd bch bck bcr bda bdb bdc bdd bdh bdk bdr bha bhb bhc bhd bhh bhk bhr bka bkb bkc bkk bkr bra brb brd brh brk brr c-- caa cab cac cad cah cak car cba cbb cbc cbd cbh cbk cbr cca ccb ccc ccd cch cck ccr cda cdb cdc cdd cdh cdk cdr ch- cha chb chc chd chh chk chr cka ckb ckc ckd ckh cra crb crc crd crh crk crr daa dab dac dad dah dak dar dba dbb dbc dbd dbh dbk dbr dca dcb dcc dcd dck dcr dda ddb ddc ddd ddh ddk ddr dh- dha dhb dhc dhd dhh dhk dhr dka dkb dkc dkk dkr dra drb drc drd drk drr haa hab hac had hah hak har hba hbb hbc hbd hbh hbk hbr hca hcb hcc hcd hch hck hcr hda hdb hdc hdd hdh hdk hdr hha hhb hhc hhd hhh hhk hhr hka hkb hkd hkh hkk hkr hr- hra hrb hrc hrd hrh hrk hrr ka- kaa kab kac kad kah kak kar kba kbb kbc kbd kbh kbk kbr kca kcb kcc kcd kch kck kcr kda kdb kdc kdh kdk kdr kha khh khk khr kkb kkc kkh kkk kkr kra krc krd krk krr ra- raa rab rac rad rah rak rar rba rbb rbc rbd rbh rbk rbr rca rcb rcc rcd rch rcr rda rdb rdc rdd rdh rdr rh- rha rhb rhc rhd rhh rhr rkb rkc rkk rra rrb rrc rrd rrh rrk rrr