1. Create a class to implement a Stack providing all appropriate operations in the class, use so that you can use the same class for integer stack and character stack.

1. Write a driver program which gives user an option:

• To write an expression (infix/postfix) in an output file.
• To read an infix expression from a file and check its validity.
• To read a valid infix expression from a file and convert it into a postfix expression and write it in an output file.
• To read a postfix expression from a file and evaluate it and display its value on console.

1. Create separate functions for each of the task above. Stack class implementation can be dynamic or static.