a-a a-b a-c aaa aab aac aad aah aas ab- aba abb abc abd abh abs ac- aca acb acc acd ach acs ad- ada adb adc add adh ads aha ahb ahc ahd ahh ahs as- asa asb asc asd ash ass baa bab bac bad bah bas bba bbb bbc bbd bbh bbs bca bcb bcc bcd bch bcs bda bdb bdc bdd bdh bds bha bhb bhc bhd bhh bhs bsa bsb bsc bsd bsh bss c-- caa cab cac cad cah cas cba cbb cbc cbd cbh cbs cca ccb ccc ccd cch ccs cda cdb cdc cdd cdh cds ch- cha chb chc chd chh chs csa csb csc csd csh css daa dab dac dad dah das dba dbb dbc dbd dbh dbs dca dcb dcc dcd dcs dda ddb ddc ddd ddh dds dh- dha dhb dhc dhd dhh dhs dsa dsb dsc dsd dsh dss haa hab hac had hah has hba hbb hbc hbd hbh hbs hca hcb hcc hcd hch hcs hda hdb hdc hdd hdh hds hha hhb hhc hhd hhh hhs hsa hsb hsc hsd hsh hss saa sab sac sad sah sas sba sbb sbc sbd sbh sbs sca scb scc scd sch scs sda sdb sdc sdd sdh sds sh- sha shb shc shd shh shs ss- ssa ssb ssc ssd ssh sss