a-a a-b a-i aaa aab aai aam aao aap aar aas ab- aba abb abi abm abo abp abr abs ai- aia aib aii aim aio aip air ais ama amb ami amm amo amp amr ams aoa aob aoi aom aoo aop aor aos ap- apa apb api apm apo app apr aps ar- ara arb ari arm aro arp arr ars as- asa asb asi asm aso asp asr ass b-p baa bab bai bam bao bap bar bas bba bbb bbi bbm bbo bbp bbr bbs bi- bia bib bii bim bio bip bir bis bma bmb bmi bmm bmo bmp bmr bms boa bob boi bom boo bop bor bos bpa bpb bpi bpm bpo bpp bpr bps bra brb bri brm bro brp brr brs bsa bsb bsi bsm bso bsp bsr bss ia- iaa iab iai iam iao iap iar ias iba ibb ibi ibm ibo ibp ibr ibs iia iib iii iim iio iip iir iis im- ima imb imi imm imo imp ims io- ioa iob ioi iom ioo iop ior ios ipa ipb ipi ipm ipo ipp ipr ips ir- ira irb iri irm iro irp irr irs is- isa isb isi ism iso isp isr iss m-o m-r maa mab mai mam mao map mar mas mba mbb mbi mbm mbo mbp mbr mbs mi- mia mib mii mim mio mip mir mis mma mmb mmi mmm mmo mmp mmr mms moa mob moi mom moo mop mor mos mpa mpb mpi mpm mpo mpp mpr mps mra mrb mri mrm mro mrp mrr mrs msa msb msi msm mso msp msr mss o-i oaa oab oai oam oao oap oar oas ob- oba obb obi obm obo obp obr obs oia oib oii oim oio oip oir ois om- oma omb omi omm omo omp omr oms oo- ooa oob ooi oom ooo oop oor oos op- opa opb opi opm opo opp opr ops or- ora orb ori orm oro orp orr ors os- osa osb osi osm oso osp osr oss p-p paa pab pai pam pao pap par pas pba pbb pbi pbm pbo pbp pbr pbs pia pib pii pim pio pip pir pis pma pmb pmi pmm pmo pmp pmr pms poa pob poi pom poo pop por pos ppa ppb ppi ppm ppo ppp ppr pps pra prb pri prm pro prp prr prs ps- psa psb psi psm pso psp psr pss ra- raa rab rai ram rao rap rar ras rba rbb rbi rbm rbo rbp rbr rbs ria rib rii rim rio rip rir ris rma rmb rmi rmm rmo rmp rmr rms roa rob roi rom roo rop ror ros rpa rpb rpi rpm rpo rpp rpr rps rra rrb rri rrm rrp rrr rrs rsa rsb rsi rsm rso rsp rsr rss saa sab sai sam sao sap sar sas sba sbb sbi sbm sbo sbp sbr sbs sia sib sii sim sio sip sir sis sma smb smi smm smo smp smr sms soa sob soi som soo sop sor sos spa spb spi spm spo spp spr sps sr- sra srb sri srm sro srp srr srs ss- ssa ssb ssi ssm sso ssp ssr sss