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

Laplace transforms, There actually isn't all that much to this section. All...

There actually isn't all that much to this section. All we are going to do now is work a quick illustration using Laplace transforms for a 3 rd order differential equation therefo

Create a raptor program - use class in raptor and in python, In this porti...

In this portion of the lab you will analyze a problem and create a Raptor program to solve it.  Make sure you use a class in Raptor and in Python to solve the problem.  Read the fo

how to store multidimensional array in a single column in m, how to store ...

how to store multidimensional array in a single column in mysql database using MATLAB?

Version control system, Version Control is a critical tool in development a...

Version Control is a critical tool in development and production environments that allows a user to make snapshots of working con?gurations or code. In this assignment, you will de

Program for connect 4 game on a general board, The classical connect-4 game...

The classical connect-4 game is played on a 67 board, it can in fact be played in any nrRowsnrCols board. In your implementation, the user will specify the number of rows nrRows an

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

Matlab and Image Processing and Neural Network, I need to do image reconstr...

I need to do image reconstruction using Neural Network using Matlab

Asp.net support for ajax and javascript intellisense, ASP.NET Support for A...

ASP.NET Support for AJAX and JavaScript IntelliSense IntelliSense for Enthusiasm JScript makes it accessible client-script selection components in the value manager in Vision Facil

Java, Write a program that repeatedly prompts for and reads a positive inte...

Write a program that repeatedly prompts for and reads a positive integer value n and then calculates and displays the nth Fibonacci number

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