c-- ccc ccn cco ccs cct cn- cnc cnn cno cns cnt co- coc con coo cos cot csc csn cso css cst ctc ctn cto cts ctt ncc ncn nco ncs nct nnc nnn nno nns nnt no- noc non noo nos not nsc nsn nso nss nst ntc ntn nto nts ntt oc- occ ocn oco ocs oct on- onc onn ono ons ont oo- ooc oon ooo oos oot os- osc osn oso oss ost ot- otc otn oto ots ott scc scn sco scs sct snc snn sno sns snt soc son soo sos sot ss- ssc ssn sso sss sst stc stn sto sts stt tcc tcn tco tcs tct tnc tnn tno tns tnt to- toc ton too tos tot tsc tsn tso tss tst ttc ttn tto tts ttt