a-a a-b a-z aaa aab aad aam aaz ab- aba abb abd abm abz ad- ada adb add adm adz ama amb amd amm amz az- aza azb azd azm azz baa bab bad bam baz bba bbb bbd bbm bda bdb bdd bdm bdz bma bmb bmd bmm bmz bza bzd bzz daa dab dad dam daz dba dbb dbd dbm dbz dda ddb ddd ddm ddz dma dmb dmd dmm dmz dza dzb dzd maa mab mad mam maz mba mbb mbd mbm mda mdb mdd mdm mdz mma mmb mmd mmm mmz mza mzb mzm zaa zab zad zam zaz zbb zbm zdm zma zmb zmd zmm zzz