c-- ccc ccd cce cco cct ccv cdc cdd cde cdo cdt cdv ce- cec ced cee ceo cet cev co- coc cod coe coo cot cov ctc ctd cte cto ctt ctv cvc cvd cve cvo cvt cvv dcc dcd dce dco dct dcv ddc ddd dde ddo ddt de- dec ded dee deo det dev doc dod doe doo dot dov dtc dtd dte dto dtt dtv dvc dvd dve dvt ec- ecc ecd ece eco ect ecv ed- edc edd ede edo edt eec eed eee eeo eet eev eo- eoc eod eoe eoo eot etc etd ete eto ett etv evc evd eve evo evt evv oc- occ ocd oco oct ocv odc odd ode odo odt odv oec oed oee oeo oet oo- ooc ood ooo oot oov ot- otc otd ote oto ott otv ov- ovc ovd ove ovo ovv tcc tcd tce tco tct tcv tdc tdd tde tdo tdt tdv te- tec ted tee teo tet tev to- toc tod toe too tot tov ttc ttd tte tto ttt ttv tvc tvd tve tvo tvt v-e vcc vcd vce vco vct vdc vdd vde vdo vdt vdv vec ved vee veo vet voc vod voe voo vot vov vtc vte vto vtt vtv vvc vvo vvt vvv