a-a a-c aaa aac aaf aam aan ac- aca acc acf acm acn af- afa afc aff afm afn ama amc amf amm amn an- ana anc anf anm ann c-- caa cac caf cam can cca ccc ccf ccm ccn cfa cfc cff cfm cfn cma cmc cmf cmm cmn cn- cna cnc cnf cnm cnn faa fac faf fam fan fca fcc fcf fcm fcn ffa ffc fff ffm ffn fma fmc fmf fmm fmn fna fnc fnf fnm fnn m-f maa mac maf mam man mc- mca mcc mcf mcm mcn mfa mfc mff mfm mfn mma mmc mmf mmm mmn mna mnc mnf mnm mnn naa nac naf nam nan nca ncc ncf ncm ncn nfa nfc nff nfn nma nmc nmm nmn nna nnc nnf nnm nnn