a-a a-b a-i aaa aab aad aae aai aak aas ab- aba abb abd abe abi abk abs ad- ada adb add ade adi adk ads aea aeb aed aee aei aek aes ai- aia aib aid aie aii aik ais aka akb akd ake aki akk aks as- asa asb asd ase asi ask ass baa bab bad bae bai bak bas bba bbb bbd bbe bbi bbk bbs bda bdb bdd bde bdi bdk bds be- bea beb bed bee bei bek bes bi- bia bib bid bie bii bik bis bka bkb bke bkk bks bsa bsb bsd bse bsi bsk bss daa dab dad dae dai dak das dba dbb dbd dbe dbi dbk dbs dda ddb ddd dde ddi ddk dds de- dea deb ded dee dei dek des di- dia dib did die dii dik dis dka dkb dke dki dkk dks dsa dsb dsd dse dsi dsk dss eaa eab ead eae eai eak eas eba ebb ebd ebe ebi ebk ebs ed- eda edb edd ede edi edk eds eea eeb eed eee eek ees eia eib eid eie eii eik eis eka ekb ekd eke eki eks es- esa esb esd ese esi esk ess i-d ia- iaa iab iad iae iai ias iba ibb ibd ibe ibi ibk ibs ida idb idd ide idi idk ids ie- iea ied iee iei iek ies iia iib iid iie iii iis ika ikb ike iki ikk iks is- isa isb isd ise isi isk iss ka- kaa kab kad kae kai kak kas kba kbb kbd kbe kbi kbk kbs kda kdb kde kdk kds ke- kea keb ked kee kei kek kes kia kib kid kie kii kik kis kkb kke kki kkk kks ksa ksb ksd kse ksi ksk kss saa sab sad sae sai sak sas sba sbb sbd sbe sbi sbk sbs sda sdb sdd sde sdi sdk sds se- sea seb sed see sei sek ses sia sib sid sie sii sik sis sk- ska skb skd ske ski skk sks ss- ssa ssb ssd sse ssi ssk sss