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

Hashing and hash functions, Q. Describe the term hashing. Explain any two u...

Q. Describe the term hashing. Explain any two usually used hash functions. Explain one method of collision resolution.

State algorithm to insert node p at the end of a linked list, Algo rithm t...

Algo rithm to Insert a Node p at the End of a Linked List is explained below Step1:   [check for space] If new1= NULL output "OVERFLOW" And exit Step2:   [Allocate fr

What is an algorithm, What is an algorithm?  What are the characteristics o...

What is an algorithm?  What are the characteristics of a good algorithm? An algorithm is "a step-by-step process for accomplishing some task'' An algorithm can be given in many

Explain the array and linked list implementation of stack, Question 1. ...

Question 1. How can you find out the end of a String? Write an algorithm to find out the substring of a string. 2. Explain the insertion and deletion operation of linked lis

Define a tree and list its properties, QUESTION (a) Define a tree and l...

QUESTION (a) Define a tree and list its properties. (b) By showing all your workings, draw the spanning tree for the following graph based on the Breadth-First-Search algori

Determine the area subdivision method, Area Subdivision Method In this ...

Area Subdivision Method In this method, the viewport is examined for clear decisions on the polygons situated in it, in regard to their overlap and visibility to the viewer. Fo

Determine the output of vehicles algorithm, Draw trace table and determine ...

Draw trace table and determine the output from the below flowchart using following data (NOTE: input of the word "end" stops program and outputs results of survey):  Vehicle = c

Determine about the logic gates, Determine about the logic gates Many e...

Determine about the logic gates Many electronic circuits operate using binary logic gates. Logic gates essentially process signals that represent true or false or equivalent i.

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