-ic a-a a-b a-c a-i aaa aab aac aae aai aas ab- aba abb abc abe abi abs ac- aca acb acc ace aci acs aea aeb aec aee aei aes ai- aia aib aic aie aii ais as- asa asb asc ase asi ass baa bab bac bae bai bas bba bbb bbc bbe bbi bbs bca bcb bcc bce bci bcs be- bea beb bec bee bei bes bi- bia bib bic bie bii bis bsa bsb bsc bse bsi bss c-- caa cab cac cae cai cas cba cbb cbc cbe cbi cbs cca ccb ccc cce cci ccs ce- cea ceb cec cee cei ces ci- cia cib cic cie cii cis csa csb csc cse csi css eaa eab eac eae eai eas eba ebb ebc ebe ebi ebs ec- eca ecb ecc ece eci ecs eea eeb eec eee ees eia eib eic eie eii eis es- esa esb esc ese esi ess ia- iaa iab iac iae iai ias iba ibb ibc ibe ibi ibs ica icb icc ice ici ics ie- iea iec iee iei ies iia iib iic iie iii iis is- isa isb isc ise isi iss saa sab sac sae sai sas sba sbb sbc sbe sbi sbs sca scb scc sce sci scs se- sea seb sec see sei ses sia sib sic sie sii sis ss- ssa ssb ssc sse ssi sss