-ic a-a a-b a-c a-i aaa aab aac aai aao aap aar aas ab- aba abb abc abi abo abp abr abs ac- aca acb acc aci aco acp acr acs ai- aia aib aic aii aio aip air ais aoa aob aoc aoi aoo aop aor aos ap- apa apb apc api apo app apr aps ar- ara arb arc ari aro arp arr ars as- asa asb asc asi aso asp asr ass b-p baa bab bac bai bao bap bar bas bba bbb bbc bbi bbo bbp bbr bbs bca bcb bcc bci bco bcp bcr bcs bi- bia bib bic bii bio bip bir bis boa bob boc boi boo bop bor bos bpa bpb bpc bpi bpo bpp bpr bps bra brb bri bro brp brr brs bsa bsb bsc bsi bso bsp bsr bss c-- caa cab cac cai cao cap car cas cba cbb cbc cbi cbo cbp cbr cbs cca ccb ccc cci cco ccp ccr ccs ci- cia cib cic cii cio cip cir cis co- coa cob coc coi coo cop cor cos cpa cpb cpc cpi cpo cpp cpr cps cra crb crc cri cro crp crr crs csa csb csc csi cso csp csr css ia- iaa iab iac iai iao iap iar ias iba ibb ibc ibi ibo ibp ibr ibs ica icb icc ici ico icp icr ics iia iib iic iii iio iip iir iis io- ioa iob ioc ioi ioo iop ior ios ipa ipb ipc ipi ipo ipp ipr ips ir- ira irb irc iri iro irp irr irs is- isa isb isc isi iso isp isr iss o-i oaa oab oac oai oao oap oar oas ob- oba obb obc obi obo obp obr obs oc- oca ocb occ oci oco ocp ocr ocs oia oib oic oii oio oip oir ois oo- ooa oob ooc ooi ooo oop oor oos op- opa opb opc opi opo opp opr ops or- ora orb orc ori oro orp orr ors os- osa osb osc osi oso osp osr oss p-p paa pab pac pai pao pap par pas pba pbb pbc pbi pbo pbp pbr pbs pca pcb pcc pci pco pcp pcr pcs pia pib pic pii pio pip pir pis poa pob poc poi poo pop por pos ppa ppb ppc ppi ppo ppp ppr pps pra prb prc pri pro prp prr prs ps- psa psb psc psi pso psp psr pss ra- raa rab rac rai rao rap rar ras rba rbb rbc rbi rbo rbp rbr rbs rca rcb rcc rci rco rcp rcr rcs ria rib ric rii rio rip rir ris roa rob roc roi roo rop ror ros rpa rpb rpc rpi rpo rpp rpr rps rra rrb rrc rri rrp rrr rrs rsa rsb rsc rsi rso rsp rsr rss saa sab sac sai sao sap sar sas sba sbb sbc sbi sbo sbp sbr sbs sca scb scc sci sco scp scr scs sia sib sic sii sio sip sir sis soa sob soc soi soo sop sor sos spa spb spc spi spo spp spr sps sr- sra srb src sri sro srp srr srs ss- ssa ssb ssc ssi sso ssp ssr sss