Postfix to Infix conversation [closed]

Answer 1

It is fairly straight forward:

1. You read an argument and decide if it is a value or a variable. If it is, you push the argument on the stack. If it isn't it is an operator.
2. If you have an operator, you create a tree consisting of the operator as the root and as many arguments of the stack as its children. You push the tree on the stack.
3. When you want to print the infix notation you do an in-order walk of the top of the stack (the original post-fix notation is just a post-order walk of the same tree).

To deal with this in C++ I create a base class (Expression) with derived class representing the different kinds of nodes (Value, Variable, and BinaryOperation) and maintain a std::stack>. Coding this out is mainly a typing exercise.