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

Efficiency of linear search, Efficiency of Linear Search How much numbe...

Efficiency of Linear Search How much number of comparisons is there in this search in searching for a particular element? The number of comparisons based upon where the reco

Define null values, Define null values.  In some cases a particular ent...

Define null values.  In some cases a particular entity might not have an applicable value for an attribute or if we do not know the value of an attribute for a particular entit

Algorithm to evaluate expression given in postfix notation , Q. Write down ...

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+/+*

Files structures, The structures of files vary from operating system to ope...

The structures of files vary from operating system to operating system. In this unit, we will discuss the fundamentals of file structures with the generic file organisations. A

Avl tree rotations, AVL trees and the nodes it contains must meet strict ba...

AVL trees and the nodes it contains must meet strict balance requirements to maintain O(log n) search time. These balance restrictions are kept maintained via various rotation func

Array implementation of a queue, Since the stack is list of elements, the q...

Since the stack is list of elements, the queue is also a list of elements. The stack & the queue differ just in the position where the elements may be added or deleted. Similar to

Importance of object-oriented over java, Importance of Object-Oriented over...

Importance of Object-Oriented over java Java is basically based on OOP notions of classes and objects. Java uses a formal OOP type system that should be obeyed at compile-t

Pseudocodes, how to draw a 5 inch square on the screen using * symbol

how to draw a 5 inch square on the screen using * symbol

What is a range - a structured type in ruby, Range: A Structured Type in Ru...

Range: A Structured Type in Ruby Ruby has a numerous structured types, comprising arrays, hashes, sets, classes, streams, and ranges. In this section we would only discuss rang

Explain about the preconditions assertion, Preconditions assertion A ...

Preconditions assertion A precondition is an assertion which should be true at the initiation of an operation. For instance, a square root operation can't accept a negative a

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