a-a a-c aaa aac aap aar aas ac- aca acc acp acr acs ap- apa apc app apr aps ar- ara arc arp arr ars as- asa asc asp asr ass c-- caa cac cap car cas cca ccc ccp ccr ccs cpa cpc cpp cpr cps cra crc crp crr crs csa csc csp csr css p-p paa pac pap par pas pca pcc pcp pcr pcs ppa ppc ppp ppr pps pra prc prp prr prs ps- psa psc psp psr pss ra- raa rac rap rar ras rca rcc rcp rcr rcs rpa rpc rpp rpr rps rra rrc rrp rrr rrs rsa rsc rsp rsr rss saa sac sap sar sas sca scc scp scr scs spa spc spp spr sps sr- sra src srp srr srs ss- ssa ssc ssp ssr sss