Feature #2: Evaluate the Arithmetic Expression

Description

For this feature, you have to create a module for evaluating mathematical expressions. The expressions are already extracted from the source code and are available as strings. Your job is to compute the result and return it. The expressions are subject to the following constraints:

• The numbers can only be integers.
• For simplicity’s sake, the expressions can only contain + and - operators.
• The expression can contain () parentheses.
• The expression has already been verified as being valid.

Let’s look at an example to understand the feature specifications. Suppose the input expression is "5-(3+4)". Your program has to evaluate it following mathematical rules. First, the expression inside parentheses is solved and then the rest. The result will be the integer value -2.

Solution

This problem is a great candidate for a stack use case. But first, we need to keep in mind the rules of addition and subtraction, the precedence of parentheses, and that the spaces in ...