-up b-p b-u bbb bbc bbo bbp bbs bbu bcb bcc bco bcp bcs bcu bob boc boo bop bos bou bpb bpc bpo bpp bps bpu bsb bsc bso bsp bss bsu bub buc buo bup bus buu c-- cbb cbc cbo cbp cbs cbu ccb ccc cco ccp ccs ccu co- cob coc coo cop cos cou cpb cpc cpo cpp cps cpu csb csc cso csp css csu cub cuc cuo cup cus cuu ob- obb obc obo obp obs obu oc- ocb occ oco ocp ocs ocu oo- oob ooc ooo oop oos op- opb opc opo opp ops os- osb osc oso osp oss osu ou- ouc ouo oup ous p-p pbb pbc pbo pbp pbs pbu pcb pcc pco pcp pcs pcu pob poc poo pop pos pou ppb ppc ppo ppp pps ppu ps- psb psc pso psp pss psu pub puc pup pus puu sbb sbc sbo sbp sbs sbu scb scc sco scp scs scu sob soc soo sop sos sou spb spc spo spp sps spu ss- ssb ssc sso ssp sss ssu sub suc suo sup sus suu ubb ubc ubo ubp ubs ubu ucb ucc uco ucp ucs ucu uob uoc uoo uop uos up- upb upc upo upp ups upu usb usc uso usp uss usu uuc uus uuu