solved issue
/*
initialize t(f|e) uniformly
 do until convergence
   set count(f|e) to 0 for all f,e
   set total(e) to 0 for all e
   for all sentence pairs (f_s,e_s)
     set total_s(f) = 0 for all f     //distinct f   from f_s ?
     for all words f in f_s    
       for all words e in e_s
         total_s(f) += t(f|e)
     for all words f in f_s
       for all words e in e_s
         count(f|e) += t(f|e) / total_s(f)
         total(e)   += t(f|e) / total_s(f)
   for all e
     for all f
       t(f|e) = count(f|e) / total(e)
       
*/