c-- ccc ccd cco ccp ccs cct cdc cdd cdo cdp cds cdt co- coc cod coo cop cos cot cpc cpd cpo cpp cps cpt csc csd cso csp css cst ctc ctd cto ctp cts ctt dcc dcd dco dcp dcs dct ddc ddd ddo ddp dds ddt doc dod doo dop dos dot dpc dpd dpo dpp dps dpt dsc dsd dso dsp dss dst dtc dtd dto dtp dts dtt oc- occ ocd oco ocp ocs oct odc odd odo odp ods odt oo- ooc ood ooo oop oos oot op- opc opd opo opp ops opt os- osc osd oso osp oss ost ot- otc otd oto otp ots ott p-p pcc pcd pco pcp pcs pct pdc pdd pdo pdp pds pdt poc pod poo pop pos pot ppc ppd ppo ppp pps ppt ps- psc psd pso psp pss pst pt- ptc ptd pto ptp pts ptt scc scd sco scp scs sct sdc sdd sdo sdp sds sdt soc sod soo sop sos sot spc spd spo spp sps spt ss- ssc ssd sso ssp sss sst stc std sto stp sts stt tcc tcd tco tcp tcs tct tdc tdd tdo tdp tds tdt to- toc tod too top tos tot tpc tpd tpo tpp tps tpt tsc tsd tso tsp tss tst ttc ttd tto ttp tts ttt