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

JavaScript Language , JavaScript is "Object Oriented" like C++ or Java. (No...

JavaScript is "Object Oriented" like C++ or Java. (Note that Java and JavaScript are not the same language, which is a common misconception) It also has variables, which makes Java

Jquery, i am stuck on array part from getting response of jquery. anyone co...

i am stuck on array part from getting response of jquery. anyone could help?

Shell script convert the given amount into words, Normal 0 fals...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Introduction to javascript, This is the programming language of the Web. It...

This is the programming language of the Web. It is mainly used for validating forms. JavaScript & Java can be associated to each other. There exist several other differences betwee

Microprocessor, what is a microprocessor? types of microprocessors? advanta...

what is a microprocessor? types of microprocessors? advantages disadvantages

Pascal, how do i make a bomber game using pascal on a software called lazur...

how do i make a bomber game using pascal on a software called lazuras

Create an application to run in the amazon ec2 service, In this assignment ...

In this assignment you will create an application to run in the Amazon EC2 service and you will also create a client that can run on local machine and access your application. You

Inheritance, The Lost Bay Software Coop purchased EnviroMeasurements, a sma...

The Lost Bay Software Coop purchased EnviroMeasurements, a small startup with a product, GreenStation, that measures pollen count and air quality. The company has ventured

Write a procedure to prints the avl tree, (a) Write a procedure called (loo...

(a) Write a procedure called (lookup n t). This procedure has 2 arguments: n is the value being looked up, t is the AVL tree. The subtree with n as its root is returned (or '() if

Multi-targeting .net structure, Support for Multi-Targeting The multi-targe...

Support for Multi-Targeting The multi-targeting function of Vision Facilities allows you specify the particular edition or account of the .NET Structure that is required for your p

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