-ic a-a a-b a-c a-i aaa aab aac aae aaf aai aao ab- aba abb abc abe abf abi abo ac- aca acb acc ace acf aci aco aea aeb aec aee aef aei aeo af- afa afb afc afe aff afi afo ai- aia aib aic aie aif aii aio aoa aob aoc aoe aof aoi aoo baa bab bac bae baf bai bao bba bbb bbc bbe bbf bbi bbo bca bcb bcc bce bcf bci bco be- bea beb bec bee bef bei beo bfa bfb bfc bfe bff bfi bfo bi- bia bib bic bie bif bii bio boa bob boc boe bof boi boo c-- caa cab cac cae caf cai cao cba cbb cbc cbe cbf cbi cbo cca ccb ccc cce ccf cci cco ce- cea ceb cec cee cef cei ceo cfa cfb cfc cfe cff cfi cfo ci- cia cib cic cie cif cii cio co- coa cob coc coe cof coi coo eaa eab eac eae eaf eai eao eba ebb ebc ebe ebf ebi ebo ec- eca ecb ecc ece ecf eci eco eea eeb eec eee eef eeo ef- efa efb efc efe eff efi efo eia eib eic eie eif eii eio eo- eoa eob eoc eoe eof eoi eoo faa fab fac fae faf fai fao fba fbb fbc fbe fbf fbi fbo fca fcb fcc fce fcf fci fco fea feb fec fee fef fei feo ffa ffc ffe fff ffi ffo fia fib fic fie fif fii foa fob foc foe fof foi foo i-f ia- iaa iab iac iae iaf iai iao iba ibb ibc ibe ibf ibi ibo ica icb icc ice icf ici ico ie- iea iec iee ief iei ifa ifb ifc ife iff ifi ifo iia iib iic iie iif iii iio io- ioa iob ioc ioe iof ioi ioo o-i oaa oab oac oae oaf oai oao ob- oba obb obc obe obf obi obo oc- oca ocb occ ocf oci oco oea oeb oec oee oef oei oeo of- ofa ofb ofc ofe off ofi ofo oia oib oic oie oif oii oio oo- ooa oob ooc oof ooi ooo