fff ffi ffl ffs fft fif fii fil fis fit flf fli fll fls flt fsf fsi fsl fss fst ftf fti ftl fts ftt i-f iff ifi ifl ifs ift iif iii iil iis iit il- ilf ili ill ils ilt is- isf isi isl iss ist itf iti itl its itt lff lfi lfl lfs lft lif lii lil lis lit llf lli lll lls llt lsf lsi lsl lss lst ltf lti ltl lts ltt sff sfi sfl sfs sft sif sii sil sis sit slf sli sll sls slt ss- ssf ssi ssl sss sst stf sti stl sts stt tff tfi tfl tfs tft tif tii til tis tit tlf tli tll tls tlt tsf tsi tsl tss tst ttf tti ttl tts ttt