a-a a-b a-c aaa aab aac aam aao aas aau ab- aba abb abc abm abo abs abu ac- aca acb acc acm aco acs acu ama amb amc amm amo ams amu aoa aob aoc aom aoo aos aou as- asa asb asc asm aso ass asu au- aua aub auc aum auo aus b-u baa bab bac bam bao bas bau bba bbb bbc bbm bbo bbs bbu bca bcb bcc bcm bco bcs bcu bma bmb bmc bmm bmo bms bmu boa bob boc bom boo bos bou bsa bsb bsc bsm bso bss bsu bua bub buc bum buo bus buu c-- caa cab cac cam cao cas cau cba cbb cbc cbm cbo cbs cbu cca ccb ccc ccm cco ccs ccu cma cmb cmc cmm cmo cms cmu co- coa cob coc com coo cos cou csa csb csc csm cso css csu cua cub cuc cum cuo cus cuu m-o maa mab mac mam mao mas mau mba mbb mbc mbm mbo mbs mbu mc- mca mcb mcc mcm mco mcs mcu mma mmb mmc mmm mmo mms mmu moa mob moc mom moo mos mou msa msb msc msm mso mss msu mua mub muc mum mus muu oaa oab oac oam oao oas oau ob- oba obb obc obm obo obs obu oc- oca ocb occ ocm oco ocs ocu om- oma omb omc omm omo oms omu oo- ooa oob ooc oom ooo oos os- osa osb osc osm oso oss osu ou- oua ouc oum ouo ous saa sab sac sam sao sas sau sba sbb sbc sbm sbo sbs sbu sca scb scc scm sco scs scu sma smb smc smm smo sms smu soa sob soc som soo sos sou ss- ssa ssb ssc ssm sso sss ssu sua sub suc sum suo sus suu ua- uaa uab uac uam uao uas uau uba ubb ubc ubo ubs ubu uca ucb ucc ucm uco ucs ucu um- uma umb umc umm umo ums umu uoa uob uoc uom uoo uos usa usb usc usm uso uss usu uua uuc uum uus uuu