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

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

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

Boar corloring, Board coloring , C/C++ Programming

Board coloring , C/C++ Programming

Explain the stack, QUESTION Explain the following data structures: ...

QUESTION Explain the following data structures: (a) List (b) Stack (c) Queues Note : your explanation should consist of the definition, operations and examples.

#binary search, Ask question #Minima binary search tree is used to locate t...

Ask question #Minima binary search tree is used to locate the number 43 which of the following probe sequences are possible and which are not? explainum 100 words accepted#

Write an algorithm outputs number of books using psuedocode, A shop sells b...

A shop sells books, maps and magazines. Every item is identified by a unique 4 - digit code. All books have a code starting with a 1, all maps have a code which starts with a 2 and

Explain memory allocation strategies, Memory Allocation Strategies If i...

Memory Allocation Strategies If it is not desirable to move blocks of due storage from one area of memory to another, it must be possible to relocate memory blocks that have be

Infix expression into the postfix expression, Q. Write down an algorithm to...

Q. Write down an algorithm to convert an infix expression into the postfix expression.     Ans. Algo rithm to convert infix expression to post fix expression is given as

Data searching, In file access: what is the difference between serial, seq...

In file access: what is the difference between serial, sequential and indexed sequential searching

Fifo, give any example of page replacement using fifo and use your own refe...

give any example of page replacement using fifo and use your own reference string

Delete a given node from a doubly linked list, Algorithm to Delete a given ...

Algorithm to Delete a given node from a doubly linked list Delete a Node from Double Linked List DELETEDBL(INFO, FORW, BACK, START, AVAIL,LOC) 1. [Delete Node] Set FOR

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