a-a a-b aaa aab aad aar aas aav ab- aba abb abd abr abs abv ad- ada adb add adr ads adv ar- ara arb ard arr ars arv as- asa asb asd asr ass asv av- ava avb avd avr avs baa bab bad bar bas bav bba bbb bbd bbr bbs bda bdb bdd bdr bds bdv bra brb brd brr brs brv bsa bsb bsd bsr bss bsv bva bvb bvd bvr bvs bvv daa dab dad dar das dav dba dbb dbd dbr dbs dbv dda ddb ddd ddr dds dra drb drd drr drs drv dsa dsb dsd dsr dss dsv dva dvb dvd dvr dvs ra- raa rab rad rar ras rav rba rbb rbd rbr rbs rda rdb rdd rdr rds rdv rra rrb rrd rrr rrs rsa rsb rsd rsr rss rsv rva rvb rvd rvr rvs rvv saa sab sad sar sas sav sba sbb sbd sbr sbs sbv sda sdb sdd sdr sds sdv sr- sra srb srd srr srs srv ss- ssa ssb ssd ssr sss ssv sva svb svd svr svs svv v-a vaa vab vad var vas vav vba vbd vbr vbs vbv vdb vdd vdr vds vdv vra vrb vrd vrr vrs vsa vsb vsd vsr vss vsv vva vvb vvr vvs vvv