# unambiguous expression grammar with parens
# python chart.py -q -i " ( int + int ) * int"

exp -> exp addop term
exp -> term

term -> term mulop factor
term -> factor

factor -> open_paren exp close_paren
factor -> number

# lexical rules 
open_paren -> (
close_paren -> )
number -> int
addop -> +
addop -> -
mulop -> *
mulop -> /