a-a a-b a-c a-t aaa aab aac aad aak aat ab- aba abb abc abd abk abt ac- aca acb acc acd ack act ad- ada adb adc add adk adt aka akb akc akd akk at- ata atb atc atd att baa bab bac bad bak bat bba bbb bbc bbd bbk bbt bca bcb bcc bcd bck bct bda bdb bdc bdd bdk bdt bka bkb bkc bkk bkt bta btb btc btd btk btt c-- caa cab cac cad cak cat cba cbb cbc cbd cbk cbt cca ccb ccc ccd cck cct cda cdb cdc cdd cdk cdt cka ckb ckc ckd ckt cta ctb ctc ctd ctk ctt daa dab dac dad dak dat dba dbb dbc dbd dbk dbt dca dcb dcc dcd dck dct dda ddb ddc ddd ddk ddt dka dkb dkc dkk dkt dta dtb dtc dtd dtk dtt k-t ka- kaa kab kac kad kak kat kba kbb kbc kbd kbk kca kcb kcc kcd kck kct kda kdb kdc kdk kdt kkb kkc kkk kkt kta ktb ktc ktk ktt taa tab tac tad tak tat tba tbb tbc tbd tbk tbt tca tcb tcc tcd tck tct tda tdb tdc tdd tdk tdt tka tkb tkc tkk tkt tta ttb ttc ttd ttk ttt