c-- ccc cco ccp ccs cct co- coc coo cop cos cot cpc cpo cpp cps cpt csc cso csp css cst ctc cto ctp cts ctt oc- occ oco ocp ocs oct oo- ooc ooo oop oos oot op- opc opo opp ops opt os- osc oso osp oss ost ot- otc oto otp ots ott p-p pcc pco pcp pcs pct poc poo pop pos pot ppc ppo ppp pps ppt ps- psc pso psp pss pst pt- ptc pto ptp pts ptt scc sco scp scs sct soc soo sop sos sot spc spo spp sps spt ss- ssc sso ssp sss sst stc sto stp sts stt tcc tco tcp tcs tct to- toc too top tos tot tpc tpo tpp tps tpt tsc tso tsp tss tst ttc tto ttp tts ttt