c-- ccc ccn cco ccr cct cn- cnc cnn cno cnr cnt co- coc con coo cor cot crc crn cro crr crt ctc ctn cto ctr ctt ncc ncn nco ncr nct nnc nnn nno nnt no- noc non noo nor not nrc nrn nro nrr nrt ntc ntn nto ntr ntt oc- occ ocn oco ocr oct on- onc onn ono onr ont oo- ooc oon ooo oor oot or- orc orn oro orr ort ot- otc otn oto otr ott rcc rcn rco rcr rct rnc rnn rno rnr rnt roc ron roo ror rot rrc rrn rrr rrt rtc rtn rto rtr rtt tcc tcn tco tcr tct tnc tnn tno tnr tnt to- toc ton too tor tot trc trn tro trr trt ttc ttn tto ttr ttt