Postfix expression algorithm, Data Structure & Algorithms

Assignment Help:

Write an algorithm to calculate a postfix expression.  Execute your algorithm using the given postfix expression as your input : a b + c d +*f ↑ .

To evaluate a postfix expression by using the given values:

clear the stack

symb  = next input character while(not end of input)

{

if (symb is an operand)

push onto the stack;

else

{

pop two operands from the stack;

result=op1 symb op2;

push result onto the stack;

}

symb = next input character;

}

return (pop (stack));

The input postfix expression is given as:- ab+cd+*f^

Symb                 Stack                                          Evaluation a    a

b                    a b

+                   pop a and b                                 (a + b) Push (a + b)

c                    (a + b) c

d                   (a + b) c d

+                   pop c and d                                 (c + d) Push (c + d)

*                    pop (a + b) and (c + d)                (a + b) * (c + d)

f                    (a + b) * (c + d) f

^                    pop (a + b) * (c + d) and f           (a + b) * (c + d) ^ f

The result of evaluation is ((a + b) * (c + d)) ^ f


Related Discussions:- Postfix expression algorithm

Generate a single sorted list of all n elements, Q. Assume that we have sep...

Q. Assume that we have separated n elements in to m sorted lists. Explain how to generate a single sorted list of all n elements in time O (n log m )?

Write an algorithm insert, Q. Write an algorithm INSERT which takes a point...

Q. Write an algorithm INSERT which takes a pointer to a sorted list and a pointer to a node and inserts the node into its correct position or place in the list.  Ans: /* s

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

Explain class p problems, Explain class P problems Class  P  is  a  cla...

Explain class P problems Class  P  is  a  class  of  decision  problems  that  can  be  solved  in  polynomial time  by(deterministic) algorithms. This class of problems is kno

#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#

Determine the precondition of a binary search, Determine the precondition o...

Determine the precondition of a binary search For instance, precondition of a binary search is that array searched is sorted however checking this precondition is so expensive

Naïve recursive algorithm for binomial coefficients, How many recursive cal...

How many recursive calls are called by the naïve recursive algorithm for binomial coefficients, C(10, 5) and C(21, 12) C(n,k){c(n-1,k)+c(n-1,k-1) if 1 1 if k = n or k = 0

Applications of linear and binary search, The searching method are applicab...

The searching method are applicable to a number of places in current's world, may it be Internet, search engines, text pattern matching, on line enquiry, finding a record from data

Tic Tac Toe game , Book to refer: Introduction to Algorithms, 3rd Ed, by Cl...

Book to refer: Introduction to Algorithms, 3rd Ed, by Clifford Stein, Thomas H. Cormen, Ronald Rivest, Charles E. Leiserson Question: Tic Tac Toe game -Design a GUI and implement

Write algorithm for post-order traversal, P os t - o r d e r T ...

P os t - o r d e r T r av er sal :  This can be done by both iteratively and recursively. The iterative solution would require a modification or alteration of the in-

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