Expression Tree, Programming Languages

Assignment Help:
For this assignment you will read a file expression.txt and create an expression tree. The expression will be a valid infix expression with the all the necessary parentheses so that there is no ambiguity in the order of the expression. You will evaluate the expression and print the result. You will also write the prefix and postfix versions of the same expression without any parentheses.

In an expression tree the nodes are either operators or operands. The operators will be in the set [''+'', ''-'', ''*'', ''/'']. The operands will be either integers or floating point numbers. All the operand nodes will be leaves of the expression tree. All the operator nodes will have exactly two children.

The outline of your program will be as follows:

class Stack (object):

class Node (object):

class Tree (object):
def __init__ (self):

def createTree (self, expr):

def evaluate (self, aNode):

def preOrder (self, aNode):

def postOrder (self, aNode):

def main():

main()
The function createTree() will take as input parameter an infix expression with parentheses as a String and create an Expression Tree from it. Assume that the expression string is valid.

You will take the expression string and break it into tokens. There are four different kinds of tokens - left parenthesis, right parenthesis, operator, and operand. When we read a left parenthesis we are starting a new expression and when we read a right parenthesis we are ending an expression. Here is the algorithm that you will use:

If the current token is a left parenthesis add a new node as the left child of the current node. Push current node on the stack and make current node equal to the left child.
If the current token is an operator set the current node''s data value to the operator. Push current node on the stack. Add a new node as the right child of the current node and make the current node equal to the right child.
If the current token is an operand, set the current node''s data value to the operand and make the current node equal to the parent by popping the stack.
If the current token is a right parenthesis make the current node equal to the parent node by popping the stack if it is not empty.
For the input file this is what your program will output:

( ( 8 + 3 ) * ( 7 - 2 ) ) = 55

Prefix Expression: * + 8 3 - 7 2

Postfix Expression: 8 3 + 7 2 - *

Related Discussions:- Expression Tree

Included applications, Hi, Can any of you, tell me how to use Included Ap...

Hi, Can any of you, tell me how to use Included Applications?

Write a program to show ten buttons with five possible color, Write a progr...

Write a program to show ten buttons with five possible colors: red, green, orange, yellow, blue. When the user clicks on a button, its color must advance to the next color, or go b

Input output program, Problem Specification I/O programming is the \bre...

Problem Specification I/O programming is the \bread and butter", the raison d'etre, of microcontrollers. After all, our definition of a microcontroller is \a microprocessor wit

Linux assignment , Hi how can I upload my hw to you experts?

Hi how can I upload my hw to you experts?

Fortran source code, For this programming assignment, you are to develop a ...

For this programming assignment, you are to develop a Fortran 90/95/2003 program to automate a useful task. The aim of the assignment is for you to reveal your competence in the Fo

Matlab help, I am working on a matlab project and need help debugging one q...

I am working on a matlab project and need help debugging one question i have written and need help working through another problem.

Program for implement xslt, The aim of this task is to gain experience in u...

The aim of this task is to gain experience in using the popular Web languages XSLT, XQuery, DTD, XML Schema and RDF. The Content: The University is organizing a stage show wh

Write a program to handle a book collection, Write a program to handle a bo...

Write a program to handle a book collection. The data on each book might be title, author, publication date, book number and  cataloging details. Allow for adding or deleting books

Pascal, Problem Solving 1. Write Pascal code that accepts as input the nam...

Problem Solving 1. Write Pascal code that accepts as input the names of the students, course work score and exam score for a unspecified number of students who have taken a subjec

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd