Postfix expression algorithm, Data Structure & Algorithms

Assignment Help:

Write an algorithm to calculate a postfix expression.  Execute your algorithm using the given postfix expression as your input : a b + c d +*f ↑ .

To evaluate a postfix expression by using the given values:

clear the stack

symb  = next input character while(not end of input)

{

if (symb is an operand)

push onto the stack;

else

{

pop two operands from the stack;

result=op1 symb op2;

push result onto the stack;

}

symb = next input character;

}

return (pop (stack));

The input postfix expression is given as:- ab+cd+*f^

Symb                 Stack                                          Evaluation a    a

b                    a b

+                   pop a and b                                 (a + b) Push (a + b)

c                    (a + b) c

d                   (a + b) c d

+                   pop c and d                                 (c + d) Push (c + d)

*                    pop (a + b) and (c + d)                (a + b) * (c + d)

f                    (a + b) * (c + d) f

^                    pop (a + b) * (c + d) and f           (a + b) * (c + d) ^ f

The result of evaluation is ((a + b) * (c + d)) ^ f


Related Discussions:- Postfix expression algorithm

Tower of hanoi problem., Write an algorithm for getting solution to the Tow...

Write an algorithm for getting solution to the Tower's of Hanoi problem. Explain the working of your algorithm (with 4 disks) with appropriate diagrams. Ans: void Hanoi(int

Tree structure, We would like to implement a 2-4Tree containing distinct in...

We would like to implement a 2-4Tree containing distinct integer keys. This 2-4Tree is defined by the ArrayList Nodes of all the 2-4Nodes in the tree and the special 2-4Node Root w

Visual Basic Assignment, When writing a code for a program that basically a...

When writing a code for a program that basically answers Relative Velocity questions how do you go at it? How many conditions should you go through?

What are circular queues, What are circular queues?  Circular queue: St...

What are circular queues?  Circular queue: Static queues have a very large drawback that once the queue is FULL, even though we erase few elements from the "front" and relieve

Algorithm, Define what an algorithm is and outline the characteristics of a...

Define what an algorithm is and outline the characteristics of a good algorithm.

Data Structure, Ask consider the file name cars.text each line in the file ...

Ask consider the file name cars.text each line in the file contains information about a car ( year,company,manufacture,model name,type) 1-read the file 2-add each car which is repr

BST has two children, If a node in a BST has two children, then its inorder...

If a node in a BST has two children, then its inorder predecessor has No right child

Relative and direct files, Each data record contains a fixed place in a rel...

Each data record contains a fixed place in a relative file. Each record ought to have associated with it in integer key value which will help identify this slot. Therefore, this ke

Multiple queue, What is multiple queue and explain them

What is multiple queue and explain them

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