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

Write a perl program to design a computer game, Write a Perl program ghici....

Write a Perl program ghici.pl, one of the simplest computer games. The program should generate a random integer between 1 and 1000 and asks the user to guess it. If the user ?nds t

Oracle, What is "No_Data_Found" in Oracle?

What is "No_Data_Found" in Oracle?

Develop a context diagram and use case diagram, Develop (i) a context diagr...

Develop (i) a context diagram and (ii) a use case diagram to model the following functionalities of NetFlix. Netflix is an online video/DVD renting company. A customer desiring

Program to explore page replacement algorithms, Objective: The purpose of ...

Objective: The purpose of this programming project is to explore page replacement algorithms. This can be accomplished by developing a simple simulator that implements various pag

Program to find the largest value in an array, 1. Write out a detailed plan...

1. Write out a detailed plan for a program to find the largest value in an array that is smaller than a ceiling C. For example, suppose the array has the values {4, 14, 11, 100, 6}

Shell script toconvert all lowercase to uppercase characters, Normal 0 ...

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

Algorithm to enumerate a fingerprint, Let S =  {s 1 , s 2 , .... , s k } de...

Let S =  {s 1 , s 2 , .... , s k } denote a set of k genomes. The problem of fingerprinting is the task of identifying a shortest possible substring α i from each string si such t

Ado. net, ADO. NET ADO.NET (ActiveX Information Things for .NET) is a set o...

ADO. NET ADO.NET (ActiveX Information Things for .NET) is a set of programs elements that developers can use to accessibility data and data solutions. It is an element of the platf

Shell script to print left traingle, Normal 0 false false f...

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

Write c sharp application to read a data, A number of simple student record...

A number of simple student records are written to a text file. The format of some typical linesshould be - Task (1): Using a text editor, create a file with 10 such reco

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