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

The complexity of multiplying two matrices, The complexity of multiplying t...

The complexity of multiplying two matrices of order m*n and n*p is    mnp

Add the special form let to the metacircular interpreter, (1)  (i) Add the ...

(1)  (i) Add the special form let to the metacircular interpreter Hint: remember let is just syntactic sugar for a lambda expression and so a rewrite to the lambda form is all t

Progrrame, how to write a code for for a company , for calculate the salary...

how to write a code for for a company , for calculate the salary pay

Addressing modes, Compare zero-address, one-address, two-address, and three...

Compare zero-address, one-address, two-address, and three-address machines by writing programs to compute: Y = (A – B X C) / (D + E X F) for each of the four machines. The inst

Random searching, write aprogram for random -search to implement if a[i]=x;...

write aprogram for random -search to implement if a[i]=x;then terminate other wise continue the search by picking new randon inex into a

Algorithm for determining who won rock paper scissors game, Suppose you are...

Suppose you are given the results of 5 games of rock-paper-scissors. The results are given to you on separate pieces of paper; each piece says either 'A' if the first person won, o

Union & intersection of two linklist, how to write an algorithm for unions ...

how to write an algorithm for unions & intersection of two linklists?

Linked list, write an algorithm for multiplication of two sparse matrices u...

write an algorithm for multiplication of two sparse matrices using Linked Lists

Define queue fifo ?, A queue is a particular type of collection or abstract...

A queue is a particular type of collection or abstract data type in which the entities in the collection are went in order and the principal functions on the collection are the add

Determine the space complexity of euclid algorithm, 1)      Why space compl...

1)      Why space complexity is comparatively more critical than time complexity? 2)      Determine the space complexity of Euclid Algorithm?

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