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

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

What is assertions and abstract data types, Assertions and Abstract Data Ty...

Assertions and Abstract Data Types Even though we have defined assertions in terms of programs, notion can be extended to abstract data types (which are mathematical entities).

Algorithms, b) The user will roll two (six-sided) dices and the user will l...

b) The user will roll two (six-sided) dices and the user will lose the game if (s)he gets a value 1 on either any of the two dices & wins otherwise. Display a message to the user w

Define data model, Define data model?  A data model is a collection of ...

Define data model?  A data model is a collection of conceptual tools for explaning data, data relationships, data semantics and consistency constraints.

Determine the algorithm for z-buffer method, Algorithm for Z-Buffer Method ...

Algorithm for Z-Buffer Method (a)  Initialize every pixel in the viewport to the smallest value of z, namely z0 the z-value of the rear clipping plane or "back-ground". Store a

Enumerate about the carrier set members, Enumerate about the carrier set me...

Enumerate about the carrier set members Ruby is written in C, so carrier set members (which is, individual symbols) are implemented as fixed-size arrays of characters (which is

Total weight of minimum spanning tree, a) Run your program for α = 0.05, 0...

a) Run your program for α = 0.05, 0.5, and 0.95. You can use n = 30, and W = 10. What is impact of increasing value of α on connectivity of G'? To answer this question, for each v

Progrrame, how to write a code for for a company , for calculate the salary...

how to write a code for for a company , for calculate the salary pay

Cohen sutherland algorithm, Using the cohen sutherland. Algorithm. Find the...

Using the cohen sutherland. Algorithm. Find the visible portion of the line P(40,80) Q(120,30) inside the window is defined as ABCD A(20,20),B(60,20),C(60,40)and D(20,40)

What is ruby, What is Ruby Ruby has numerous simple types, including nu...

What is Ruby Ruby has numerous simple types, including numeric classes such as Integer, Fixnum, Bignum, Float, Big Decimal, Rational, and Complex, textual classes like String,

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