c-- ccc ccf ccm cco ccr ccs cct cfc cff cfm cfo cfr cfs cft cmc cmf cmm cmo cmr cms cmt co- coc cof com coo cor cos cot crc crf crm cro crr crs crt csc csf csm cso csr css cst ctc ctf ctm cto ctr cts ctt fcc fcf fcm fco fcr fcs fct ffc fff ffm ffo ffr ffs fft fmc fmf fmm fmo fmr fms fmt foc fof fom foo for fos fot frc frf frm fro frr frs frt fsc fsf fsm fso fsr fss fst ftc ftf ftm fto ftr fts ftt m-f m-o m-r mc- mcc mcf mcm mco mcr mcs mct mfc mff mfm mfo mfr mfs mft mmc mmf mmm mmo mmr mms mmt moc mof mom moo mor mos mot mrc mrf mrm mro mrr mrs mrt msc msf msm mso msr mss mst mtc mtf mtm mto mtr mts mtt oc- occ ocf ocm oco ocr ocs oct of- ofc off ofm ofo ofr ofs oft om- omc omf omm omo omr oms omt oo- ooc oof oom ooo oor oos oot or- orc orf orm oro orr ors ort os- osc osf osm oso osr oss ost ot- otc otf otm oto otr ots ott rcc rcf rcm rco rcr rcs rct rfc rff rfm rfo rfr rfs rft rmc rmf rmm rmo rmr rms rmt roc rof rom roo ror ros rot rrc rrf rrm rrr rrs rrt rsc rsf rsm rso rsr rss rst rtc rtf rtm rto rtr rts rtt scc scf scm sco scr scs sct sfc sff sfm sfo sfr sfs sft smc smf smm smo smr sms smt soc sof som soo sor sos sot sr- src srf srm sro srr srs srt ss- ssc ssf ssm sso ssr sss sst stc stf stm sto str sts stt tcc tcf tcm tco tcr tcs tct tfc tff tfm tfo tfr tfs tft tmc tmf tmm tmo tmr tms tmt to- toc tof tom too tor tos tot trc trf trm tro trr trs trt tsc tsf tsm tso tsr tss tst ttc ttf ttm tto ttr tts ttt