Algorithm to evaluate expression given in postfix notation , Data Structure & Algorithms

Assignment Help:

Q. Write down an algorithm to evaluate an expression given to you in postfix notation. Show the execution of your algorithm for the following given expression.

AB^CD-EF/GH+/+*                                                                               

Ans.

Algorithm to evaluate Post fix Expression is shown as follows

 

Opndstk = the empty stack;

/*scan the input string reading one */

/*element at a time into symb */

while ( not end of input){

symb  = next input character;

if (symb is an operand)

push (opndstk, symb);

else

{

/* symb is an operator */

opnd 2 = Pop (opnd stk);

opnd 1 = Pop (opnd stk);

value = result of applying symb to opnd 1 and opnd 2;

push (opndstk,value);

}/*end else */

}/*end while */

return (pop (opnd stk));

AB^CD-EF/GH+/+*

Symb

Opnd1

Opnd2

Value

Opndstk

A

 

 

 

A

B

 

 

 

A,B

^

A

B

A^B

A^B

C

A

B

A^B

A^B,C

D

A

B

A^B

A^B,C,D

-

C

D

C-D

A^B,C-D

E

C

D

C-D

A^B,C-D,E

F

C

D

C-D

A^B,C-D,E,F

/

E

F

E/F

A^B,C-D,E/F

G

E

F

E/F

A^B,C-D,E/F,G

H

E

F

E/F

A^B,C-D,E/F,G,H

+

G

H

G+H

A^B,C-D,E/F,G+H

/

E/F

G+H

(E/F)/(G+H)

A^B,C-D, (E/F) /(G+H)

+

C-D

(E/F)/(G+H)

(C-D)+(E/F)/(G+H)

A^B,(C-D)+

(E/F)/(G+H)

*

A^B

(C-

D)+(E/F)/(G+H)

A^B*((C-D)+

(E/F)/(G+H))

A^B*((C-D)+

(E/F)/(G+H))


Related Discussions:- Algorithm to evaluate expression given in postfix notation

Algorithm that counts number of nodes in a linked list, Q. Write an algorit...

Q. Write an algorithm that counts number of nodes in a linked list.                                       A n s . Algo rithm to Count No. of Nodes in Linked List C

Determine the stereo vision, Determine the stereo vision There is still...

Determine the stereo vision There is still one more major item missing, before we can look at a computer display or plot and perceive it just as we see a real object, namely th

Stack, infix to revrse polish

infix to revrse polish

What are the structures used in file-system implementation, What are the st...

What are the structures used in file-system implementation? Several on-disk and in-memory structures are used to execute a file system a. On-disk structure include P

Applications in file systems of avl trees, 1. In computer science, a classi...

1. In computer science, a classic problem is how to dynamically store information so as to let for quick look up. This searching problem arises frequently in dictionaries, symbol t

Adjacency matrix of an undirected graph, 1) What will call a graph that hav...

1) What will call a graph that have no cycle? 2) Adjacency matrix of an undirected graph is------------- on main diagonal. 3) Represent the following graphs by adjacency matr

Explain binary search tree, Binary search tree. A binary search tree is...

Binary search tree. A binary search tree is a binary tree that is either empty or in which every node having a key that satisfies the following conditions: - All keys (if an

Algorithm, Ask question #MWhich of the following is not a characteristic of...

Ask question #MWhich of the following is not a characteristic of good algorithm? inimum 100 words accepted#

Write procedure to the insert a node into the linked list, Q. Write a proce...

Q. Write a procedure to the insert a node into the linked list at a particular position and draw the same by taking an example?

Function performs multiplication of two numbers, You need to write a functi...

You need to write a function that performs multiplication of two numbers in your data structure. Again, remember how you multiply numbers in base 10 and you should be fine. Multipl

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