Matching math expression with regular expression?

Question

For example, these are valid math expressions:

a * b + c
-a * (b / 1.50)
(apple + (-0.5)) * (boy - 1)

And these are invalid math expression

Answer 1

For parenthesis matching, and implementing other expression validation rules, it is probably easiest to write your own little parser. Regular expressions are no good in this kind of situation.