ddd ddf ddm ddo dds ddt dfd dff dfm dfo dfs dft dmd dmf dmm dmo dms dmt dod dof dom doo dos dot dsd dsf dsm dso dss dst dtd dtf dtm dto dts dtt fdd fdf fdm fdo fds fdt ffd fff ffm ffo ffs fft fmd fmf fmm fmo fms fmt fof fom foo fos fot fsd fsf fsm fso fss fst ftd ftf ftm fto fts ftt m-f m-o mdd mdf mdm mdo mds mdt mfd mff mfm mfo mfs mft mmd mmf mmm mmo mms mmt mod mof mom moo mos mot msd msf msm mso mss mst mtd mtf mtm mto mts mtt odd odf odm odo ods odt of- ofd off ofm ofo ofs oft om- omd omf omm omo oms omt oo- ood oof oom ooo oos oot os- osd osf osm oso oss ost ot- otd otf otm oto ots ott sdd sdf sdm sdo sds sdt sfd sff sfm sfo sfs sft smd smf smm smo sms smt sod sof som soo sos sot ss- ssd ssf ssm sso sss sst std stf stm sto sts stt tdd tdf tdm tdo tds tdt tfd tff tfm tfo tfs tft tmd tmf tmm tmo tms tmt to- tod tof tom too tos tot tsd tsf tsm tso tss tst ttd ttf ttm tto tts ttt