exp -> exp addop term
exp -> term
addop -> +
addop -> -
term -> term mulop factor
term -> factor
mulop -> *
factor -> ( exp )
factor -> number

The Follow Set:
Follow(exp) = { $, +, -, ) }
Follow(addop) = { (, number }
Follow(term) = { $, +, -, *, ) }
Follow(mulop) = { (, number }
Follow(factor) = { $, +, -, *, ) }