a-a a-b a-c aaa aab aac aae aag aas ab- aba abb abc abe abg abs ac- aca acb acc ace acg acs aea aeb aec aee aeg aes ag- aga agb agc age agg ags as- asa asb asc ase asg ass baa bab bac bae bag bas bba bbb bbc bbe bbg bbs bca bcb bcc bce bcg bcs be- bea beb bec bee beg bes bga bgb bgc bge bgg bgs bsa bsb bsc bse bsg bss c-- caa cab cac cae cag cas cba cbb cbc cbe cbg cbs cca ccb ccc cce ccg ccs ce- cea ceb cec cee ceg ces cga cgb cgc cge cgg cgs csa csb csc cse csg css eaa eab eac eae eag eas eba ebb ebc ebe ebg ebs ec- eca ecb ecc ece ecg ecs eea eeb eec eee eeg ees ega egb egc ege egg egs es- esa esb esc ese esg ess gaa gab gac gae gag gas gba gbc gbe gbg gbs gca gcb gcc gce gcg gcs ge- gea geb gec gee geg ges gga ggb ggc ggg ggs gsa gsb gsc gse gsg gss saa sab sac sae sag sas sba sbb sbc sbe sbg sbs sca scb scc sce scg scs se- sea seb sec see seg ses sga sgb sgc sge sgg sgs ss- ssa ssb ssc sse ssg sss