fff ffl ffs fft ffu flf fll fls flt flu fsf fsl fss fst fsu ftf ftl fts ftt ftu fuf ful fus fut fuu lff lfl lfs lft lfu llf lll lls llt llu lsf lsl lss lst lsu ltf ltl lts ltt ltu luf lul lus lut luu sff sfl sfs sft sfu slf sll sls slt slu ss- ssf ssl sss sst ssu stf stl sts stt stu suf sul sus sut suu tff tfl tfs tft tfu tlf tll tls tlt tlu tsf tsl tss tst tsu ttf ttl tts ttt ttu tuf tul tus tut tuu uff ufl ufs uft ufu ulf ull uls ult ulu usf usl uss ust usu utf utl uts utt utu uus uut uuu