a-a a-b a-c aaa aab aac aae aas aau ab- aba abb abc abe abs abu ac- aca acb acc ace acs acu aea aeb aec aee aes aeu as- asa asb asc ase ass asu au- aua aub auc aue aus b-u baa bab bac bae bas bau bba bbb bbc bbe bbs bbu bca bcb bcc bce bcs bcu be- bea beb bec bee bes beu bsa bsb bsc bse bss bsu bua bub buc bue bus buu c-- caa cab cac cae cas cau cba cbb cbc cbe cbs cbu cca ccb ccc cce ccs ccu ce- cea ceb cec cee ces ceu csa csb csc cse css csu cua cub cuc cue cus cuu eaa eab eac eae eas eau eba ebb ebc ebe ebs ebu ec- eca ecb ecc ece ecs ecu eea eeb eec eee ees es- esa esb esc ese ess esu eu- eua eub euc eue eus saa sab sac sae sas sau sba sbb sbc sbe sbs sbu sca scb scc sce scs scu se- sea seb sec see ses seu ss- ssa ssb ssc sse sss ssu sua sub suc sue sus suu ua- uaa uab uac uae uas uau uba ubb ubc ube ubs ubu uca ucb ucc uce ucs ucu uea ueb uec uee ues usa usb usc use uss usu uua uuc uue uus uuu