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

Data structure, Ask question #Minimum 1Mark each of the following statement...

Ask question #Minimum 1Mark each of the following statements as valid or invalid. If a statement is invalid, explain why. a. current ¼ list; b. temp->link->link ¼ NULL; c. trail->l

Mathematical-model with a collection of operations, A mathematical-model wi...

A mathematical-model with a collection of operations described on that model is known as??? Abstract Data Type

Binary search trees, A Binary Search Tree is binary tree which is either em...

A Binary Search Tree is binary tree which is either empty or a node having a key value, left child & right child. By analyzing the above definition, we notice that BST comes int

Compound interest, Write the algorithm for compound interest

Write the algorithm for compound interest

Algorithm for similar binary tree, Q. The two Binary Trees are said to be s...

Q. The two Binary Trees are said to be similar if they are both empty or if they are both non- empty and left and right sub trees are similar. Write down an algorithm to determine

Java code and algorythem, Suppose that you want to develop a program that a...

Suppose that you want to develop a program that accepts a postfix expression and asks values for variables in the expression. Then you need to calculate the answer for the expressi

Recursion, difference between recursion and iteration

difference between recursion and iteration

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

Boundary tag method in context of dynamic memory management, Q. How can we ...

Q. How can we free the memory by using Boundary tag method in the context of Dynamic memory management?

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