-th bbb bbc bbh bbo bbt bby bcb bcc bch bco bct bcy bhb bhc bhh bho bht bob boc boh boo bot boy btb btc bth bto btt bty by- byc byh byo byt c-- cbb cbc cbh cbo cbt cby ccb ccc cch cco cct ch- chb chc chh cho cht chy co- cob coc coh coo cot coy ctb ctc cth cto ctt cty cyb cyc cyo cyt hbb hbc hbh hbo hbt hby hcb hcc hch hco hct hcy hhb hhc hhh hho hht hhy hob hoc hoh hoo hot hoy htb htc hth hto htt hty hy- hyb hyc hyh hyo hyt hyy ob- obb obc obh obo obt oby oc- ocb occ och oco oct ohc ohh oho oht oo- oob ooc ooh ooo oot ot- otb otc oth oto ott oyo tbb tbc tbh tbo tbt tcb tcc tch tco tct th- thb thc thh tho tht thy to- tob toc toh too tot toy ttb ttc tth tto ttt tty tyc tyo tyt ybc yby ycc ych yco ycy yhc yht yob yoc yoo yot yoy ytc yth yto ytt yyb yyc yyt yyy