a-a a-b a-c aaa aab aac aae aag aah aan aao ab- aba abb abc abe abg abh abn abo ac- aca acb acc ace acg ach acn aco aea aeb aec aee aeg aeh aen aeo ag- aga agb agc age agg agh agn ago aha ahb ahc ahe ahg ahh ahn aho an- ana anb anc ane ang anh ann ano aoa aob aoc aoe aog aoh aon aoo baa bab bac bae bag bah ban bao bba bbb bbc bbe bbg bbh bbn bbo bca bcb bcc bce bcg bch bcn bco be- bea beb bec bee beg beh ben beo bga bgb bgc bge bgg bgh bgn bgo bha bhb bhc bhe bhg bhh bho bna bnb bnc bne bng bnn bno boa bob boc boe bog boh bon boo c-- caa cab cac cae cag cah can cao cba cbb cbc cbe cbg cbh cbn cbo cca ccb ccc cce ccg cch ccn cco ce- cea ceb cec cee ceg ceh cen ceo cga cgb cgc cge cgg cgh cgn cgo ch- cha chb chc che chg chh chn cho cn- cna cnb cnc cne cng cnh cnn cno co- coa cob coc coe cog coh con coo eaa eab eac eae eag eah ean eao eba ebb ebc ebe ebg ebh ebn ebo ec- eca ecb ecc ece ecg ech ecn eco eea eeb eec eee eeg een eeo ega egb egc ege egg egh egn ego eha ehb ehc ehe ehg ehh ehn eho en- ena enb enc ene eng enh enn eno eo- eoa eob eoc eoe eog eoh eon eoo gaa gab gac gae gag gah gan gao gba gbc gbe gbg gbh gbn gbo gca gcb gcc gce gcg gch gcn gco ge- gea geb gec gee geg geh gen geo gga ggb ggc ggg ggh ggn ggo gha ghb ghc ghe ghg ghh ghn gho gna gnb gnc gne gnn gno goa gob goc goe gog goh gon goo haa hab hac hae hag hah han hao hba hbb hbc hbe hbg hbh hbn hbo hca hcb hcc hce hcg hch hcn hco he- hea heb hec hee heg heh hen heo hga hgb hgc hge hgg hgh hgn hgo hha hhb hhc hhe hhg hhh hhn hho hna hnb hnc hne hng hnh hnn hno hoa hob hoc hoe hog hoh hon hoo naa nab nac nae nag nah nan nao nba nbb nbc nbe nbg nbn nbo nca ncb ncc nce ncg nch ncn nco ne- nea neb nec nee neg neh nen neo nga ngb ngc nge ngg ngh ngn ngo nha nhb nhc nhe nhg nhh nhn nna nnb nnc nne nng nnh nnn nno no- noa nob noc noe nog noh non noo oaa oab oac oae oag oah oan oao ob- oba obb obc obe obg obh obn obo oc- oca ocb occ ocg och ocn oco oea oeb oec oee oeg oeh oen oeo oga ogc oge ogg ogh ogn ogo oha ohc ohe ohg ohh ohn oho on- ona onb onc one ong onh onn ono oo- ooa oob ooc oog ooh oon ooo