-er a-a a-b a-c aaa aab aac aae aah aar aas ab- aba abb abc abe abh abr abs ac- aca acb acc ace ach acr acs aea aeb aec aee aeh aer aes aha ahb ahc ahe ahh ahr ahs ar- ara arb arc are arh arr ars as- asa asb asc ase ash asr ass baa bab bac bae bah bar bas bba bbb bbc bbe bbh bbr bbs bca bcb bcc bce bch bcr bcs be- bea beb bec bee beh ber bes bha bhb bhc bhe bhh bhr bhs bra brb bre brh brr brs bsa bsb bsc bse bsh bsr bss c-- caa cab cac cae cah car cas cba cbb cbc cbe cbh cbr cbs cca ccb ccc cce cch ccr ccs ce- cea ceb cec cee ceh cer ces ch- cha chb chc che chh chr chs cra crb crc cre crh crr crs csa csb csc cse csh csr css eaa eab eac eae eah ear eas eba ebb ebc ebe ebh ebr ebs ec- eca ecb ecc ece ech ecr ecs eea eeb eec eee eer ees eha ehb ehc ehe ehh ehr ehs era erb erc ere erh err ers es- esa esb esc ese esh esr ess haa hab hac hae hah har has hba hbb hbc hbe hbh hbr hbs hca hcb hcc hce hch hcr hcs he- hea heb hec hee heh her hes hha hhb hhc hhe hhh hhr hhs hr- hra hrb hrc hre hrh hrr hrs hsa hsb hsc hse hsh hsr hss ra- raa rab rac rae rah rar ras rba rbb rbc rbe rbh rbr rbs rca rcb rcc rce rch rcr rcs re- rea reb rec ree reh rer res rh- rha rhb rhc rhe rhh rhr rhs rra rrb rrc rrh rrr rrs rsa rsb rsc rse rsh rsr rss saa sab sac sae sah sar sas sba sbb sbc sbe sbh sbr sbs sca scb scc sce sch scr scs se- sea seb sec see seh ser ses sh- sha shb shc she shh shr shs sr- sra srb src sre srh srr srs ss- ssa ssb ssc sse ssh ssr sss