-er a-a a-b a-c aaa aab aac aad aae aaf aah aar ab- aba abb abc abd abe abf abh abr ac- aca acb acc acd ace acf ach acr ad- ada adb adc add ade adf adh adr aea aeb aec aed aee aef aeh aer af- afa afb afc afd afe aff afh afr aha ahb ahc ahd ahe ahf ahh ahr ar- ara arb arc ard are arf arh arr baa bab bac bad bae baf bah bar bba bbb bbc bbd bbe bbf bbh bbr bca bcb bcc bcd bce bcf bch bcr bda bdb bdc bdd bde bdf bdh bdr be- bea beb bec bed bee bef beh ber bfa bfb bfc bfd bfe bff bfh bfr bha bhb bhc bhd bhe bhf bhh bhr bra brb brd bre brf brh brr c-- caa cab cac cad cae caf cah car cba cbb cbc cbd cbe cbf cbh cbr cca ccb ccc ccd cce ccf cch ccr cda cdb cdc cdd cde cdf cdh cdr ce- cea ceb cec ced cee cef ceh cer cfa cfb cfc cfd cfe cff cfh cfr ch- cha chb chc chd che chf chh chr cra crb crc crd cre crf crh crr daa dab dac dad dae daf dah dar dba dbb dbc dbd dbe dbf dbh dbr dca dcb dcc dcd dce dcf dcr dda ddb ddc ddd dde ddf ddh ddr de- dea deb dec ded dee def deh der dfa dfb dfc dfd dfe dff dfh dfr dh- dha dhb dhc dhd dhe dhf dhh dhr dra drb drc drd dre drr eaa eab eac ead eae eaf eah ear eba ebb ebc ebd ebe ebf ebh ebr ec- eca ecb ecc ecd ece ecf ech ecr ed- eda edb edc edd ede edf edh edr eea eeb eec eed eee eef eer ef- efa efb efc efd efe eff efh efr eha ehb ehc ehd ehe ehf ehh ehr era erb erc erd ere erf erh err faa fab fac fad fae faf fah far fba fbb fbc fbd fbe fbf fbh fbr fca fcb fcc fcd fce fcf fcr fda fdb fdc fdd fde fdf fdh fdr fea feb fec fed fee fef feh fer ffa ffc ffd ffe fff ffh ffr fha fhb fhc fhe fhf fhh fhr fra frb frc frd fre frf frh frr haa hab hac had hae haf hah har hba hbb hbc hbd hbe hbf hbh hbr hca hcb hcc hcd hce hcf hch hcr hda hdb hdc hdd hde hdf hdh hdr he- hea heb hec hed hee hef heh her hfa hfb hfc hfd hfe hff hfh hfr hha hhb hhc hhd hhe hhf hhh hhr hr- hra hrb hrc hrd hre hrf hrh hrr ra- raa rab rac rad rae raf rah rar rba rbb rbc rbd rbe rbf rbh rbr rca rcb rcc rcd rce rcf rch rcr rda rdb rdc rdd rde rdf rdh rdr re- rea reb rec red ree ref reh rer rfa rfb rfc rfd rfe rff rfh rfr rh- rha rhb rhc rhd rhe rhf rhh rhr rra rrb rrc rrd rrf rrh rrr