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

Shell script to display words of a file in ascending order, Normal 0 ...

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

SRGP, Implement the pull-down menu package

Implement the pull-down menu package

Linux Lab Assignments, I have a linux lab class that consist of 1 lab assig...

I have a linux lab class that consist of 1 lab assignment per week for 5 weeks. It is an online virtual lab and is fairly easy, I just don''t have the time.

I got a project and i need help , the details on the two pictures on the li...

the details on the two pictures on the link below : http://rak-up.com/up/files/18637.jpg ">http://rak-up.com/up/files/18636.jpg http://rak-up.com/up/files/18637.jpg

Shell script to count characters, Normal 0 false false fals...

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

Extensive programming platform .net, Extensive programming platform .NET ...

Extensive programming platform .NET It is a new, simple, and comprehensive selection foundation. It is not a selection terminology, but it can handle several selection dialects.

ARM LANGUAGE, I WANT TO MAKE PROJECT IN ARM LANGUAGE CAN YOU HELP ME

I WANT TO MAKE PROJECT IN ARM LANGUAGE CAN YOU HELP ME

STM32, Windows XP using C# load a binary file and send it thru a USB port t...

Windows XP using C# load a binary file and send it thru a USB port to the USB port of STM32. STM32 received the file and then write it into an I2C EEPROM.

Write a program to illustrate the call by value, Write a Program to illustr...

Write a Program to illustrate the call by value? #include . int compute_sum(int m); int main( void) { int n=3, sum; printf("%d\n",n); /*3 is printed */ sum=compute_sum(n

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