a-a a-b a-i aaa aab aae aag aai aas ab- aba abb abe abg abi abs aea aeb aee aeg aei aes ag- aga agb age agg agi ags ai- aia aib aie aig aii ais as- asa asb ase asg asi ass baa bab bae bag bai bas bba bbb bbe bbg bbi bbs be- bea beb bee beg bei bes bga bgb bge bgg bgi bgs bi- bia bib bie big bii bis bsa bsb bse bsg bsi bss eaa eab eae eag eai eas eba ebb ebe ebg ebi ebs eea eeb eee eeg ees ega egb ege egg egi egs eia eib eie eig eii eis es- esa esb ese esg esi ess gaa gab gae gag gai gas gba gbe gbg gbi gbs ge- gea geb gee geg gei ges gga ggb ggg ggi ggs gia gib gie gig gii gis gsa gsb gse gsg gsi gss ia- iaa iab iae iag iai ias iba ibb ibe ibg ibi ibs ie- iea iee ieg iei ies iga igb ige igg igi igs iia iib iie iii iis is- isa isb ise isg isi iss saa sab sae sag sai sas sba sbb sbe sbg sbi sbs se- sea seb see seg sei ses sga sgb sge sgg sgi sgs sia sib sie sig sii sis ss- ssa ssb sse ssg ssi sss