a-a a-b a-i a-t aaa aab aad aaf aai aat ab- aba abb abd abf abi abt ad- ada adb add adf adi adt af- afa afb afd aff afi aft ai- aia aib aid aif aii ait at- ata atb atd atf ati att baa bab bad baf bai bat bba bbb bbd bbf bbi bbt bda bdb bdd bdf bdi bdt bfa bfb bfd bff bfi bft bi- bia bib bid bif bii bit bta btb btd btf bti btt daa dab dad daf dai dat dba dbb dbd dbf dbi dbt dda ddb ddd ddf ddi ddt dfa dfb dfd dff dfi dft di- dia dib did dif dii dit dta dtb dtd dtf dti dtt faa fab fad faf fai fat fba fbb fbd fbf fbi fbt fda fdb fdd fdf fdi fdt ffa ffd fff ffi fft fia fib fid fif fii fit fta ftb ftd ftf fti ftt i-d i-f ia- iaa iab iad iaf iai iat iba ibb ibd ibf ibi ibt ida idb idd idf idi idt ifa ifb ifd iff ifi ift iia iib iid iif iii iit ita itb itd itf iti itt taa tab tad taf tai tat tba tbb tbd tbf tbi tbt tda tdb tdd tdf tdi tdt tfa tfb tfd tff tfi tft tia tib tid tif tii tit tta ttb ttd ttf tti ttt