-ey bbb bbc bbe bbo bbt bby bcb bcc bce bco bct bcy be- beb bec bee beo bet bey bob boc boe boo bot boy btb btc bte bto btt bty by- byc bye byo byt c-- cbb cbc cbe cbo cbt cby ccb ccc cce cco cct ce- ceb cec cee ceo cet cey co- cob coc coe coo cot coy ctb ctc cte cto ctt cty cyb cyc cye cyo cyt ebb ebc ebe ebo ebt eby ec- ecb ecc ece eco ect eeb eec eee eeo eet eey eo- eob eoc eoe eoo eot etb etc ete eto ett ety eyc eye eyo eyt ob- obb obc obe obo obt oby oc- ocb occ oco oct oeb oec oee oeo oet oey oo- oob ooc ooo oot ot- otb otc ote oto ott oye oyo tbb tbc tbe tbo tbt tcb tcc tce tco tct te- teb tec tee teo tet tey to- tob toc toe too tot toy ttb ttc tte tto ttt tty tyc tye tyo tyt ybc ybe yby ycc yce yco ycy yeb yec yee yeo yet yey yob yoc yoe yoo yot yoy ytc yte yto ytt yyb yyc yye yyt yyy