-ic a-a a-b a-c a-i aaa aab aac aaf aai aan aao aar ab- aba abb abc abf abi abn abo abr ac- aca acb acc acf aci acn aco acr af- afa afb afc aff afi afn afo afr ai- aia aib aic aif aii ain aio air an- ana anb anc anf ani ann ano anr aoa aob aoc aof aoi aon aoo aor ar- ara arb arc arf ari arn aro arr baa bab bac baf bai ban bao bar bba bbb bbc bbf bbi bbn bbo bbr bca bcb bcc bcf bci bcn bco bcr bfa bfb bfc bff bfi bfn bfo bfr bi- bia bib bic bif bii bin bio bir bna bnb bnc bnf bni bnn bno bnr boa bob boc bof boi bon boo bor bra brb brf bri brn bro brr c-- caa cab cac caf cai can cao car cba cbb cbc cbf cbi cbn cbo cbr cca ccb ccc ccf cci ccn cco ccr cfa cfb cfc cff cfi cfn cfo cfr ci- cia cib cic cif cii cin cio cir cn- cna cnb cnc cnf cni cnn cno cnr co- coa cob coc cof coi con coo cor cra crb crc crf cri crn cro crr faa fab fac faf fai fan fao far fba fbb fbc fbf fbi fbn fbo fbr fca fcb fcc fcf fci fcn fco fcr ffa ffc fff ffi ffn ffo ffr fia fib fic fif fii fin fir fna fnb fnc fnf fni fnn fnr foa fob foc fof foi fon foo for fra frb frc frf fri frn fro frr i-f ia- iaa iab iac iaf iai ian iao iar iba ibb ibc ibf ibi ibn ibo ibr ica icb icc icf ici icn ico icr ifa ifb ifc iff ifi ifn ifo ifr iia iib iic iif iii iin iio iir in- ina inb inc inf ini inn ino inr io- ioa iob ioc iof ioi ion ioo ior ir- ira irb irc irf iri irn iro irr n-i naa nab nac naf nai nan nao nar nba nbb nbc nbf nbi nbn nbo nbr nca ncb ncc ncf nci ncn nco ncr nfa nfb nfc nff nfi nfn nfo nfr nia nib nic nif nii nin nio nir nna nnb nnc nnf nni nnn nno no- noa nob noc nof noi non noo nor nra nrb nrc nrf nri nrn nro nrr o-i oaa oab oac oaf oai oan oao oar ob- oba obb obc obf obi obn obo obr oc- oca ocb occ ocf oci ocn oco ocr of- ofa ofb ofc off ofi ofn ofo ofr oia oib oic oif oii oin oio oir on- ona onb onc onf oni onn ono onr oo- ooa oob ooc oof ooi oon ooo oor or- ora orb orc orf ori orn oro orr ra- raa rab rac raf rai ran rao rar rba rbb rbc rbf rbi rbn rbo rbr rca rcb rcc rcf rci rcn rco rcr rfa rfb rfc rff rfi rfn rfo rfr ria rib ric rif rii rin rio rir rna rnb rnc rni rnn rno rnr roa rob roc rof roi ron roo ror rra rrb rrc rrf rri rrn rrr