-ic a-a a-b a-c a-i aaa aab aac aad aae aai aak aas ab- aba abb abc abd abe abi abk abs ac- aca acb acc acd ace aci ack acs ad- ada adb adc add ade adi adk ads aea aeb aec aed aee aei aek aes ai- aia aib aic aid aie aii aik ais aka akb akc akd ake aki akk aks as- asa asb asc asd ase asi ask ass baa bab bac bad bae bai bak bas bba bbb bbc bbd bbe bbi bbk bbs bca bcb bcc bcd bce bci bck bcs bda bdb bdc bdd bde bdi bdk bds be- bea beb bec bed bee bei bek bes bi- bia bib bic bid bie bii bik bis bka bkb bkc bke bkk bks bsa bsb bsc bsd bse bsi bsk bss c-- caa cab cac cad cae cai cak cas cba cbb cbc cbd cbe cbi cbk cbs cca ccb ccc ccd cce cci cck ccs cda cdb cdc cdd cde cdi cdk cds ce- cea ceb cec ced cee cei cek ces ci- cia cib cic cid cie cii cik cis cka ckb ckc ckd cki cks csa csb csc csd cse csi csk css daa dab dac dad dae dai dak das dba dbb dbc dbd dbe dbi dbk dbs dca dcb dcc dcd dce dci dck dcs dda ddb ddc ddd dde ddi ddk dds de- dea deb dec ded dee dei dek des di- dia dib dic did die dii dik dis dka dkb dkc dke dki dkk dks dsa dsb dsc dsd dse dsi dsk dss eaa eab eac ead eae eai eak eas eba ebb ebc ebd ebe ebi ebk ebs ec- eca ecb ecc ecd ece eci eck ecs ed- eda edb edc edd ede edi edk eds eea eeb eec eed eee eek ees eia eib eic eid eie eii eik eis eka ekb ekc ekd eke eki eks es- esa esb esc esd ese esi esk ess i-d ia- iaa iab iac iad iae iai ias iba ibb ibc ibd ibe ibi ibk ibs ica icb icc icd ice ici ick ics ida idb idc idd ide idi idk ids ie- iea iec ied iee iei iek ies iia iib iic iid iie iii iis ika ikb ikc ike iki ikk iks is- isa isb isc isd ise isi isk iss ka- kaa kab kac kad kae kai kak kas kba kbb kbc kbd kbe kbi kbk kbs kca kcb kcc kcd kce kci kck kcs kda kdb kdc kde kdk kds ke- kea keb kec ked kee kei kek kes kia kib kic kid kie kii kik kis kkb kkc kke kki kkk kks ksa ksb ksc ksd kse ksi ksk kss saa sab sac sad sae sai sak sas sba sbb sbc sbd sbe sbi sbk sbs sca scb scc scd sce sci sck scs sda sdb sdc sdd sde sdi sdk sds se- sea seb sec sed see sei sek ses sia sib sic sid sie sii sik sis sk- ska skb skc skd ske ski skk sks ss- ssa ssb ssc ssd sse ssi ssk sss