C++ PROGRAMING
Implement a program to evaluate simple mathematical expressions.
Assume that the original expression is provided to the program as a
text string. Allowed expression tokens: brackets “(” and “)”,
integers like “4”, “15”, addition “+”, subtraction “-”,
multiplication “*”, division “/”. Output can be float. Trim spaces
from an expression. Brackets should contain at least one operation.
Make sure that an expression is validated before it is calculated;
reject the invalid expressions with appropriate message. The
program must...