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

Explain about the doubly linked list with neat diagram, Problem 1. Expl...

Problem 1. Explain about the doubly linked list with neat diagram. Diagram Explaining doubly linked list 2. Explain what are the criteria to be used in evaluatin

Non-recursive algorithm to traverse a tree in preorder, Write the non-recur...

Write the non-recursive algorithm to traverse a tree in preorder.    The Non- Recursive algorithm for preorder traversal is as follows: Initially  push NULL onto stack and

Infix expression into the postfix expression, Q. Convert the given infix ex...

Q. Convert the given infix expression into the postfix expression (also Show the steps) A ∗ (B + D)/ E - F(G + H / k ) Ans. Steps showing Infix to Post fix

What is assertions, What is Assertions Introduction At every point...

What is Assertions Introduction At every point in a program, there are generally constraints on the computational state that should hold for program to be correct. For ins

Sorting, Retrieval of information is made simpler when it is stored into so...

Retrieval of information is made simpler when it is stored into some predefined order. Therefore, Sorting is a very important computer application activity. Several sorting algorit

Structured programming, What do you understand by term structured programmi...

What do you understand by term structured programming? Explain the structured programming as well.                                 Ans. S tructured Programming is expla

Tic Tac Toe game , Book to refer: Introduction to Algorithms, 3rd Ed, by Cl...

Book to refer: Introduction to Algorithms, 3rd Ed, by Clifford Stein, Thomas H. Cormen, Ronald Rivest, Charles E. Leiserson Question: Tic Tac Toe game -Design a GUI and implement

Hotel reservation system, pls i want a psuedo code for hotel reservation sy...

pls i want a psuedo code for hotel reservation system.

Multiple stacks in a single array, implement multiple stacks in an array an...

implement multiple stacks in an array and write different algorithms to perform operations on it

Difference between prism''s and kruskal''s algorithm, Difference among Pris...

Difference among Prism's and Kruskal's Algorithm In Kruskal's algorithm, the set A is a forest. The safe edge added to A is always a least-weight edge in the paragraph that lin

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