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

Perform inorder, QUESTION (a) Construct a binary tree for the following...

QUESTION (a) Construct a binary tree for the following numbers assuming that a number greater than the node (starting from the root) goes to the left else it goes to the right.

Algorithm.., write an algorithm to sort given numbers in ascending order us...

write an algorithm to sort given numbers in ascending order using bubble sort

Define linked list ?, Linked lists are among the most common and easiest da...

Linked lists are among the most common and easiest data structures. They may be used to implement various other common abstract data types, including queues, stacks, symbolic expre

Applications of the queue, Write down any four applications of the queues. ...

Write down any four applications of the queues.                                                            Ans. A pp li cation of Queue is given below (i)  Queue is

Total impedent of the circuit, an electrical student designed a circuit in...

an electrical student designed a circuit in which the impedence in one part of a series circuit is 2+j8 ohms and the impedent is another part of the circuit is 4-j60 ohm mm program

Define wire-frame model, Define Wire-frame Model This skeletal view is ...

Define Wire-frame Model This skeletal view is called a Wire-frame Model. Although not a realistic representation  of the object, it is still very useful in the early stages of

ALGORITHMS, WRITE AN ALGORITHM TO READ TWO NUMBERS AND PRINT THE LOWER VALU...

WRITE AN ALGORITHM TO READ TWO NUMBERS AND PRINT THE LOWER VALUE

Representation of data structure in memory, Representation of data structur...

Representation of data structure in memory is known as: Abstract data type

Algorithm, algorithm to search a node in linked list

algorithm to search a node in linked list

Nested for loop, nested for loop for (i = 0; i for (j = 0; j seq...

nested for loop for (i = 0; i for (j = 0; j sequence of statements } } Here, we observe that, the outer loop executes n times. Every time the outer loop execute

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