a-a a-b a-c aaa aab aac aag aao aas aav ab- aba abb abc abg abo abs abv ac- aca acb acc acg aco acs acv ag- aga agb agc agg ago ags agv aoa aob aoc aog aoo aos aov as- asa asb asc asg aso ass asv av- ava avb avc avg avo avs baa bab bac bag bao bas bav bba bbb bbc bbg bbo bbs bca bcb bcc bcg bco bcs bcv bga bgb bgc bgg bgo bgs bgv boa bob boc bog boo bos bov bsa bsb bsc bsg bso bss bsv bva bvb bvc bvg bvo bvs bvv c-- caa cab cac cag cao cas cav cba cbb cbc cbg cbo cbs cbv cca ccb ccc ccg cco ccs ccv cga cgb cgc cgg cgo cgs cgv co- coa cob coc cog coo cos cov csa csb csc csg cso css csv cva cvb cvc cvg cvo cvs cvv gaa gab gac gag gao gas gav gba gbc gbg gbo gbs gbv gca gcb gcc gcg gco gcs gga ggb ggc ggg ggo ggs ggv goa gob goc gog goo gos gov gsa gsb gsc gsg gso gss gsv gva gvb gvc gvg gvo gvs oaa oab oac oag oao oas oav ob- oba obb obc obg obo obs obv oc- oca ocb occ ocg oco ocs ocv oga ogc ogg ogo ogs oo- ooa oob ooc oog ooo oos oov os- osa osb osc osg oso oss osv ov- ova ovb ovc ovo ovs ovv saa sab sac sag sao sas sav sba sbb sbc sbg sbo sbs sbv sca scb scc scg sco scs scv sga sgb sgc sgg sgo sgs sgv soa sob soc sog soo sos sov ss- ssa ssb ssc ssg sso sss ssv sva svb svc svg svo svs svv v-a vaa vab vac vag vao vas vav vba vbc vbg vbo vbs vbv vca vcc vco vcs vga vgc vgg vgo vgs voa vob voc vog voo vos vov vsa vsb vsc vsg vso vss vsv vva vvb vvc vvg vvo vvs vvv