-ic a-a a-b a-c a-i aaa aab aac aai aan aao aar aas ab- aba abb abc abi abn abo abr abs ac- aca acb acc aci acn aco acr acs ai- aia aib aic aii ain aio air ais an- ana anb anc ani ann ano anr ans aoa aob aoc aoi aon aoo aor aos ar- ara arb arc ari arn aro arr ars as- asa asb asc asi asn aso asr ass baa bab bac bai ban bao bar bas bba bbb bbc bbi bbn bbo bbr bbs bca bcb bcc bci bcn bco bcr bcs bi- bia bib bic bii bin bio bir bis bna bnb bnc bni bnn bno bnr bns boa bob boc boi bon boo bor bos bra brb bri brn bro brr brs bsa bsb bsc bsi bsn bso bsr bss c-- caa cab cac cai can cao car cas cba cbb cbc cbi cbn cbo cbr cbs cca ccb ccc cci ccn cco ccr ccs ci- cia cib cic cii cin cio cir cis cn- cna cnb cnc cni cnn cno cnr cns co- coa cob coc coi con coo cor cos cra crb crc cri crn cro crr crs csa csb csc csi csn cso csr css ia- iaa iab iac iai ian iao iar ias iba ibb ibc ibi ibn ibo ibr ibs ica icb icc ici icn ico icr ics iia iib iic iii iin iio iir iis in- ina inb inc ini inn ino inr ins io- ioa iob ioc ioi ion ioo ior ios ir- ira irb irc iri irn iro irr irs is- isa isb isc isi isn iso isr iss n-i naa nab nac nai nan nao nar nas nba nbb nbc nbi nbn nbo nbr nbs nca ncb ncc nci ncn nco ncr ncs nia nib nic nii nin nio nir nis nna nnb nnc nni nnn nno nns no- noa nob noc noi non noo nor nos nra nrb nrc nri nrn nro nrr nrs nsa nsb nsc nsi nsn nso nsr nss o-i oaa oab oac oai oan oao oar oas ob- oba obb obc obi obn obo obr obs oc- oca ocb occ oci ocn oco ocr ocs oia oib oic oii oin oio oir ois on- ona onb onc oni onn ono onr ons oo- ooa oob ooc ooi oon ooo oor oos or- ora orb orc ori orn oro orr ors os- osa osb osc osi osn oso osr oss ra- raa rab rac rai ran rao rar ras rba rbb rbc rbi rbn rbo rbr rbs rca rcb rcc rci rcn rco rcr rcs ria rib ric rii rin rio rir ris rna rnb rnc rni rnn rno rnr rns roa rob roc roi ron roo ror ros rra rrb rrc rri rrn rrr rrs rsa rsb rsc rsi rsn rso rsr rss saa sab sac sai san sao sar sas sba sbb sbc sbi sbn sbo sbr sbs sca scb scc sci scn sco scr scs sia sib sic sii sin sio sir sis sna snb snc sni snn sno snr sns soa sob soc soi son soo sor sos sr- sra srb src sri srn sro srr srs ss- ssa ssb ssc ssi ssn sso ssr sss