a-a a-b a-c aaa aab aac aah aau aax ab- aba abb abc abh abu abx ac- aca acb acc ach acu acx aha ahb ahc ahh ahu ahx au- aua aub auc auh aux ax- axa axh axx b-u baa bab bac bah bau bax bba bbb bbc bbh bbu bbx bca bcb bcc bch bcu bcx bha bhb bhc bhh bhu bhx bua bub buc buh buu bux bxb bxx c-- caa cab cac cah cau cax cba cbb cbc cbh cbu cbx cca ccb ccc cch ccu ccx ch- cha chb chc chh chu chx cua cub cuc cuh cuu cxc cxh cxx haa hab hac hah hau hax hba hbb hbc hbh hbu hbx hca hcb hcc hch hha hhb hhc hhh hhu hua hub huc huh huu hux hxc ua- uaa uab uac uah uau uba ubb ubc ubh ubu ubx uca ucb ucc uch ucu uha uhb uhc uhh uhu uua uuc uuu uxb uxc uxu xaa xac xau xbc xbx xcb xch xcx xxx