-er a-a a-b a-c aaa aab aac aad aae aak aap aar aas ab- aba abb abc abd abe abk abp abr abs ac- aca acb acc acd ace ack acp acr acs ad- ada adb adc add ade adk adp adr ads aea aeb aec aed aee aek aep aer aes aka akb akc akd ake akk akp akr aks ap- apa apb apc apd ape apk app apr aps ar- ara arb arc ard are ark arp arr ars as- asa asb asc asd ase ask asp asr ass b-p baa bab bac bad bae bak bap bar bas bba bbb bbc bbd bbe bbk bbp bbr bbs bca bcb bcc bcd bce bck bcp bcr bcs bda bdb bdc bdd bde bdk bdp bdr bds be- bea beb bec bed bee bek bep ber bes bka bkb bkc bke bkk bkp bkr bks bpa bpb bpc bpd bpe bpp bpr bps bra brb brd bre brk brp brr brs bsa bsb bsc bsd bse bsk bsp bsr bss c-- caa cab cac cad cae cak cap car cas cba cbb cbc cbd cbe cbk cbp cbr cbs cca ccb ccc ccd cce cck ccp ccr ccs cda cdb cdc cdd cde cdk cdp cdr cds ce- cea ceb cec ced cee cek cep cer ces cka ckb ckc ckd cks cpa cpb cpc cpd cpe cpk cpp cpr cps cra crb crc crd cre crk crp crr crs csa csb csc csd cse csk csp csr css daa dab dac dad dae dak dap dar das dba dbb dbc dbd dbe dbk dbp dbr dbs dca dcb dcc dcd dce dck dcp dcr dcs dda ddb ddc ddd dde ddk ddp ddr dds de- dea deb dec ded dee dek dep der des dka dkb dkc dke dkk dkp dkr dks dpa dpb dpc dpd dpe dpk dpp dpr dps dra drb drc drd dre drk drp drr drs dsa dsb dsc dsd dse dsk dsp dsr dss eaa eab eac ead eae eak eap ear eas eba ebb ebc ebd ebe ebk ebp ebr ebs ec- eca ecb ecc ecd ece eck ecr ecs ed- eda edb edc edd ede edk edp edr eds eea eeb eec eed eee eek eep eer ees eka ekb ekc ekd eke ekp ekr eks ep- epa epb epc epd epe epp epr eps era erb erc erd ere erk erp err ers es- esa esb esc esd ese esk esp esr ess ka- kaa kab kac kad kae kak kap kar kas kba kbb kbc kbd kbe kbk kbp kbr kbs kca kcb kcc kcd kce kck kcp kcr kcs kda kdb kdc kde kdk kdp kdr kds ke- kea keb kec ked kee kek kep ker kes kkb kkc kke kkk kkp kkr kks kpa kpc kpd kpe kpk kpp kpr kps kra krc krd krk krp krr krs ksa ksb ksc ksd kse ksk ksp ksr kss p-p paa pab pac pad pae pak pap par pas pba pbb pbc pbd pbe pbk pbp pbr pbs pca pcb pcc pcd pce pck pcp pcr pcs pda pdb pdc pdd pde pdk pdp pdr pds pea peb pec ped pee pek pep per pes pka pkb pkc pkd pke pkp pkr pks ppa ppb ppc ppd ppe ppk ppp ppr pps pra prb prc prd pre prk prp prr prs ps- psa psb psc psd pse psk psp psr pss ra- raa rab rac rad rae rak rap rar ras rba rbb rbc rbd rbe rbk rbp rbr rbs rca rcb rcc rcd rce rcp rcr rcs rda rdb rdc rdd rde rdp rdr rds re- rea reb rec red ree rek rep rer res rkb rkc rke rkk rkp rks rpa rpb rpc rpd rpe rpk rpp rpr rps rra rrb rrc rrd rrk rrp rrr rrs rsa rsb rsc rsd rse rsk rsp rsr rss saa sab sac sad sae sak sap sar sas sba sbb sbc sbd sbe sbk sbp sbr sbs sca scb scc scd sce sck scp scr scs sda sdb sdc sdd sde sdk sdp sdr sds se- sea seb sec sed see sek sep ser ses sk- ska skb skc skd ske skk skp skr sks spa spb spc spd spe spk spp spr sps sr- sra srb src srd sre srk srp srr srs ss- ssa ssb ssc ssd sse ssk ssp ssr sss