a-a a-b a-z aaa aab aad aas aaz ab- aba abb abd abs abz ad- ada adb add ads adz as- asa asb asd ass asz az- aza azb azd azs azz baa bab bad bas baz bba bbb bbd bbs bda bdb bdd bds bdz bsa bsb bsd bss bza bzd bzs bzz daa dab dad das daz dba dbb dbd dbs dbz dda ddb ddd dds ddz dsa dsb dsd dss dsz dza dzb dzd dzs saa sab sad sas saz sba sbb sbd sbs sda sdb sdd sds sdz ss- ssa ssb ssd sss ssz sza szd zaa zab zad zas zaz zbb zbs zds zsa zsz zzs zzz