b-u bbb bbc bbd bbo bbt bbu bcb bcc bcd bco bct bcu bdb bdc bdd bdo bdt bdu bob boc bod boo bot bou btb btc btd bto btt btu bub buc bud buo but buu c-- cbb cbc cbd cbo cbt cbu ccb ccc ccd cco cct ccu cdb cdc cdd cdo cdt cdu co- cob coc cod coo cot cou ctb ctc ctd cto ctt ctu cub cuc cud cuo cut cuu dbb dbc dbd dbo dbt dbu dcb dcc dcd dco dct dcu ddb ddc ddd ddo ddt ddu dob doc dod doo dot dou dtb dtc dtd dto dtt dtu dub duc dud duo dut ob- obb obc obd obo obt obu oc- ocb occ ocd oco oct ocu odb odc odd odo odt odu oo- oob ooc ood ooo oot ot- otb otc otd oto ott otu ou- ouc oud ouo out tbb tbc tbd tbo tbt tbu tcb tcc tcd tco tct tcu tdb tdc tdd tdo tdt tdu to- tob toc tod too tot tou ttb ttc ttd tto ttt ttu tub tuc tud tuo tut tuu ubb ubc ubo ubt ubu ucb ucc ucd uco uct ucu udb udc udd udo udt udu uob uoc uod uoo uot utb utc utd uto utt utu uuc uut uuu