-er -ic a-a a-b a-c a-i aaa aab aac aae aai aao aar aas ab- aba abb abc abe abi abo abr abs ac- aca acb acc ace aci aco acr acs aea aeb aec aee aei aeo aer aes ai- aia aib aic aie aii aio air ais aoa aob aoc aoe aoi aoo aor aos ar- ara arb arc are ari aro arr ars as- asa asb asc ase asi aso asr ass baa bab bac bae bai bao bar bas bba bbb bbc bbe bbi bbo bbr bbs bca bcb bcc bce bci bco bcr bcs be- bea beb bec bee bei beo ber bes bi- bia bib bic bie bii bio bir bis boa bob boc boe boi boo bor bos bra brb bre bri bro brr brs bsa bsb bsc bse bsi bso bsr bss c-- caa cab cac cae cai cao car cas cba cbb cbc cbe cbi cbo cbr cbs cca ccb ccc cce cci cco ccr ccs ce- cea ceb cec cee cei ceo cer ces ci- cia cib cic cie cii cio cir cis co- coa cob coc coe coi coo cor cos cra crb crc cre cri cro crr crs csa csb csc cse csi cso csr css eaa eab eac eae eai eao ear eas eba ebb ebc ebe ebi ebo ebr ebs ec- eca ecb ecc ece eci eco ecr ecs eea eeb eec eee eeo eer ees eia eib eic eie eii eio eir eis eo- eoa eob eoc eoe eoi eoo eor eos era erb erc ere eri ero err ers es- esa esb esc ese esi eso esr ess ia- iaa iab iac iae iai iao iar ias iba ibb ibc ibe ibi ibo ibr ibs ica icb icc ice ici ico icr ics ie- iea iec iee iei ier ies iia iib iic iie iii iio iir iis io- ioa iob ioc ioe ioi ioo ior ios ir- ira irb irc ire iri iro irr irs is- isa isb isc ise isi iso isr iss o-i oaa oab oac oae oai oao oar oas ob- oba obb obc obe obi obo obr obs oc- oca ocb occ oci oco ocr ocs oea oeb oec oee oei oeo oer oes oia oib oic oie oii oio oir ois oo- ooa oob ooc ooi ooo oor oos or- ora orb orc ore ori oro orr ors os- osa osb osc ose osi oso osr oss ra- raa rab rac rae rai rao rar ras rba rbb rbc rbe rbi rbo rbr rbs rca rcb rcc rce rci rco rcr rcs re- rea reb rec ree rei reo rer res ria rib ric rie rii rio rir ris roa rob roc roe roi roo ror ros rra rrb rrc rri rrr rrs rsa rsb rsc rse rsi rso rsr rss saa sab sac sae sai sao sar sas sba sbb sbc sbe sbi sbo sbr sbs sca scb scc sce sci sco scr scs se- sea seb sec see sei seo ser ses sia sib sic sie sii sio sir sis soa sob soc soe soi soo sor sos sr- sra srb src sre sri sro srr srs ss- ssa ssb ssc sse ssi sso ssr sss