-ic a-a a-b a-c a-i aaa aab aac aaf aah aai aao aas ab- aba abb abc abf abh abi abo abs ac- aca acb acc acf ach aci aco acs af- afa afb afc aff afh afi afo afs aha ahb ahc ahf ahh ahi aho ahs ai- aia aib aic aif aih aii aio ais aoa aob aoc aof aoh aoi aoo aos as- asa asb asc asf ash asi aso ass baa bab bac baf bah bai bao bas bba bbb bbc bbf bbh bbi bbo bbs bca bcb bcc bcf bch bci bco bcs bfa bfb bfc bff bfh bfi bfo bfs bha bhb bhc bhf bhh bhi bho bhs bi- bia bib bic bif bih bii bio bis boa bob boc bof boh boi boo bos bsa bsb bsc bsf bsh bsi bso bss c-- caa cab cac caf cah cai cao cas cba cbb cbc cbf cbh cbi cbo cbs cca ccb ccc ccf cch cci cco ccs cfa cfb cfc cff cfh cfi cfo cfs ch- cha chb chc chf chh chi cho chs ci- cia cib cic cif cih cii cio cis co- coa cob coc cof coh coi coo cos csa csb csc csf csh csi cso css faa fab fac faf fah fai fao fas fba fbb fbc fbf fbh fbi fbo fbs fca fcb fcc fcf fci fco fcs ffa ffc fff ffh ffi ffo ffs fha fhb fhc fhf fhh fhi fho fhs fia fib fic fif fih fii fis foa fob foc fof foh foi foo fos fsa fsb fsc fsf fsh fsi fso fss h-i haa hab hac haf hah hai hao has hba hbb hbc hbf hbh hbi hbo hbs hca hcb hcc hcf hch hci hco hcs hfa hfb hfc hff hfh hfi hfo hfs hha hhb hhc hhf hhh hhi hho hhs hia hib hic hif hih hii hio his hoa hob hoc hof hoh hoi hoo hos hsa hsb hsc hsf hsh hsi hss i-f ia- iaa iab iac iaf iah iai iao ias iba ibb ibc ibf ibh ibi ibo ibs ica icb icc icf ich ici ico ics ifa ifb ifc iff ifi ifo ifs iha ihb ihc ihf ihh ihi iho ihs iia iib iic iif iih iii iio iis io- ioa iob ioc iof ioh ioi ioo ios is- isa isb isc isf ish isi iso iss o-i oaa oab oac oaf oah oai oao oas ob- oba obb obc obf obh obi obo obs oc- oca ocb occ ocf och oci oco ocs of- ofa ofb ofc off ofi ofo ofs oha ohc ohf ohh ohi oho ohs oia oib oic oif oii oio ois oo- ooa oob ooc oof ooh ooi ooo oos os- osa osb osc osf osh osi oso oss saa sab sac saf sah sai sao sas sba sbb sbc sbf sbh sbi sbo sbs sca scb scc scf sch sci sco scs sfa sfb sfc sff sfh sfi sfo sfs sh- sha shb shc shf shh shi sho shs sia sib sic sif sih sii sio sis soa sob soc sof soh soi soo sos ss- ssa ssb ssc ssf ssh ssi sso sss