Mental block on this assignment

[jack0121]

Write a program in Java that takes as input a mathematical expression consisting of decimal numbers and the four basic mathematical operators (addition, subtraction, multiplication and division) and nested mathematical expressions, and evaluates this expression.

Some examples:
• 5 + 6 * 2
• (5 + 4) * (4 - 2)
• (4 + (2 * (2 - 1))) * 1.2

Any ideas as to how I could go about this? Any general algorithms would be good. I think you have to use a composite design pattern?

Cheers

[celerity66]

you need to convert the expression from infix to postfix and then use a stack to evaluate it. There are several examples on how to do this on the web.

[Kinda Electroni]

you need to convert the expression from infix to postfix and then use a stack to evaluate it. There are several examples on how to do this on the web.

Do you mean INORDER to POSTORDER or there is infix and postfix as well?

[celerity66]

Right... Inorder to postorder. Here is a link: Math Expression Evaluation