-ol fff ffl ffm ffo ffs fft flf fll flm flo fls flt fmf fml fmm fmo fms fmt fof fol fom foo fos fot fsf fsl fsm fso fss fst ftf ftl ftm fto fts ftt lff lfl lfm lfo lfs lft llf lll llm llo lls llt lmf lml lmm lmo lms lmt lof lol lom loo los lot lsf lsl lsm lso lss lst ltf ltl ltm lto lts ltt m-f m-o mff mfl mfm mfo mfs mft mlf mll mlm mlo mls mlt mmf mml mmm mmo mms mmt mof mol mom moo mos mot msf msl msm mso mss mst mtf mtl mtm mto mts mtt of- off ofl ofm ofo ofs oft olf oll olm olo ols olt om- omf oml omm omo oms omt oo- oof ool oom ooo oos oot os- osf osl osm oso oss ost ot- otf otl otm oto ots ott sff sfl sfm sfo sfs sft slf sll slm slo sls slt smf sml smm smo sms smt sof sol som soo sos sot ss- ssf ssl ssm sso sss sst stf stl stm sto sts stt tff tfl tfm tfo tfs tft tlf tll tlm tlo tls tlt tmf tml tmm tmo tms tmt to- tof tol tom too tos tot tsf tsl tsm tso tss tst ttf ttl ttm tto tts ttt