c-- ccc ccf ccm cco ccr cct cfc cff cfm cfo cfr cft cmc cmf cmm cmo cmr cmt co- coc cof com coo cor cot crc crf crm cro crr crt ctc ctf ctm cto ctr ctt fcc fcf fcm fco fcr fct ffc fff ffm ffo ffr fft fmc fmf fmm fmo fmr fmt foc fof fom foo for fot frc frf frm fro frr frt ftc ftf ftm fto ftr ftt m-f m-o m-r mc- mcc mcf mcm mco mcr mct mfc mff mfm mfo mfr mft mmc mmf mmm mmo mmr mmt moc mof mom moo mor mot mrc mrf mrm mro mrr mrt mtc mtf mtm mto mtr mtt oc- occ ocf ocm oco ocr oct of- ofc off ofm ofo ofr oft om- omc omf omm omo omr omt oo- ooc oof oom ooo oor oot or- orc orf orm oro orr ort ot- otc otf otm oto otr ott rcc rcf rcm rco rcr rct rfc rff rfm rfo rfr rft rmc rmf rmm rmo rmr rmt roc rof rom roo ror rot rrc rrf rrm rrr rrt rtc rtf rtm rto rtr rtt tcc tcf tcm tco tcr tct tfc tff tfm tfo tfr tft tmc tmf tmm tmo tmr tmt to- toc tof tom too tor tot trc trf trm tro trr trt ttc ttf ttm tto ttr ttt