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

Linked list implementation of a queue, The fundamental element of linked li...

The fundamental element of linked list is a "record" structure of at least two fields. The object which holds the data & refers to the next element into the list is called a node .

Interest, I=PR/12 numbers of years : Interest Rate up to 1 years : 5...

I=PR/12 numbers of years : Interest Rate up to 1 years : 5.50 Up to 5 years : 6.50 More than 5 year : 6.75 please design an algorithm based on the above information

All pairs shortest paths algorithm, In the last section, we discussed regar...

In the last section, we discussed regarding shortest path algorithm that starts with a single source and determines shortest path to all vertices in the graph. In this section, we

Threaded binary tree, i need the full concept of it... please can anyone pr...

i need the full concept of it... please can anyone provide

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

Illustrate the intervals in mathematics, Illustrate the intervals in mathem...

Illustrate the intervals in mathematics Carrier set of a Range of T is the set of all sets of values v ∈ T such that for some start value s ∈ T and end value e ∈ T, either s ≤

Threaded Binary Tree, If a node in a binary tree is not containing left or ...

If a node in a binary tree is not containing left or right child or it is a leaf node then that absence of child node can be represented by the null pointers. The space engaged by

Algorithm, what algorithms can i use for the above title in my project desi...

what algorithms can i use for the above title in my project desing and implmentation of road transport booking system

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