c-- ccc ccm cco ccr cct cmc cmm cmo cmr cmt co- coc com coo cor cot crc crm cro crr crt ctc ctm cto ctr ctt m-o m-r mc- mcc mcm mco mcr mct mmc mmm mmo mmr mmt moc mom moo mor mot mrc mrm mro mrr mrt mtc mtm mto mtr mtt oc- occ ocm oco ocr oct om- omc omm omo omr omt oo- ooc oom ooo oor oot or- orc orm oro orr ort ot- otc otm oto otr ott rcc rcm rco rcr rct rmc rmm rmo rmr rmt roc rom roo ror rot rrc rrm rrr rrt rtc rtm rto rtr rtt tcc tcm tco tcr tct tmc tmm tmo tmr tmt to- toc tom too tor tot trc trm tro trr trt ttc ttm tto ttr ttt