c-- ccc ccf cco ccr ccs cct ccu cfc cff cfo cfr cfs cft cfu co- coc cof coo cor cos cot cou crc crf cro crr crs crt cru csc csf cso csr css cst csu ctc ctf cto ctr cts ctt ctu cuc cuf cuo cur cus cut cuu fcc fcf fco fcr fcs fct fcu ffc fff ffo ffr ffs fft ffu foc fof foo for fos fot fou frc frf fro frr frs frt fru fsc fsf fso fsr fss fst fsu ftc ftf fto ftr fts ftt ftu fuf fuo fur fus fut fuu oc- occ ocf oco ocr ocs oct ocu of- ofc off ofo ofr ofs oft ofu oo- ooc oof ooo oor oos oot or- orc orf oro orr ors ort oru os- osc osf oso osr oss ost osu ot- otc otf oto otr ots ott otu ou- ouc ouf ouo our ous out rcc rcf rco rcr rcs rct rcu rfc rff rfo rfr rfs rft rfu roc rof roo ror ros rot rou rrc rrf rrr rrs rrt rru rsc rsf rso rsr rss rst rsu rtc rtf rto rtr rts rtt rtu ruc ruf ruo rur rus rut ruu scc scf sco scr scs sct scu sfc sff sfo sfr sfs sft sfu soc sof soo sor sos sot sou sr- src srf sro srr srs srt ss- ssc ssf sso ssr sss sst ssu stc stf sto str sts stt stu suc suf suo sur sus sut suu tcc tcf tco tcr tcs tct tcu tfc tff tfo tfr tfs tft tfu to- toc tof too tor tos tot tou trc trf tro trr trs trt tru tsc tsf tso tsr tss tst tsu ttc ttf tto ttr tts ttt ttu tuc tuf tuo tur tus tut tuu ucc ucf uco ucr ucs uct ucu ufc uff ufo ufr ufs uft ufu uoc uoo uor uos uot ur- urc urf uro urr urs urt uru usc usf uso usr uss ust usu utc utf uto utr uts utt utu uuc uur uus uut uuu