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

Java, how to save bulk entries at a time using collections?

how to save bulk entries at a time using collections?

Basics question, I am building wpf application and i want to install this a...

I am building wpf application and i want to install this application on a server pc and share it to other pces on a net work , my question is i have static class that contain data

Devlop personalized location based news service, The system you will develo...

The system you will develop should provide the following functionality to its users.     1.  Your system should allow the users to aggregate three different RSS feeds (they should

Advantages of java stored procedures, Advantages of java stored procedures ...

Advantages of java stored procedures Transactions Although a saved process contains SQL orders, once collected it will socialize with SQL Hosting server very diversely from

#matlab programming , 3d Interpolation using matlab from x,y, and z coordin...

3d Interpolation using matlab from x,y, and z coordinates in a csv file and reading them after that interpolating them..

assembly lang. H.W, 1- Allocate array with 32bit 100 element 2- Prompt the...

1- Allocate array with 32bit 100 element 2- Prompt the user to enter the maximum or the upper bound of the random value 3- Read the value and use it generate random numbers to init

Program for a single new-line character, The following function calls suppo...

The following function calls supposedly write a single new-line character, but some are incorrect. Identify which calls don't work and explain why.     printf("%c", '\n');

Fileless document and encryption(stegnography), code for using tree view co...

code for using tree view control and fill it with database using asp.net and language vb.net

Wsdl service architecture in uml, Design the proposed implementation using ...

Design the proposed implementation using the contract first approach and object oriented approaches.  At a minimum, you must provide an overview of the services in the service arch

Temperature Calculation system, Detailed Description: • The program will t...

Detailed Description: • The program will take temperature readings as input from user for specified number of consecutive days. • Program will store these temperature values into

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