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

Registers, what are registers? why we need register? Definition? Types? Wha...

what are registers? why we need register? Definition? Types? What registers can do for us?

Four applications or implementation of the stack, Q. Write down any four ap...

Q. Write down any four applications or implementation of the stack.                                     Ans. (i)       The Conversion of infix to postfix form (ii)

Algorithm for insertion into the circular queue, Algorithm for insertion of...

Algorithm for insertion of any element into the circular queue: Step-1: If "rear" of the queue is pointing at the last position then go to step-2 or else Step-3 Step-2: make

Parallel implementation of the raytracer, You are supposed to do the follow...

You are supposed to do the following: Write a parallel implementation of the raytracer using pthreads. Measure and compare the execution times for (i) the sequential ver

The complexity of searching an element, The complexity of searching an elem...

The complexity of searching an element from a set of n elements using Binary search algorithm is   O(log n)

Programme in c to create a single linked list, Q. Write  down a   p...

Q. Write  down a   programme  in  C  to  create  a  single  linked  list also  write the functions to do the following operations (i)  To insert a new node at the end (ii

Inorder traversal, Inorder traversal: The left sub tree is visited, then t...

Inorder traversal: The left sub tree is visited, then the node and then right sub-tree. Algorithm for inorder traversal is following: traverse left sub-tree visit node

A tree having ''m'' nodes has (m-1) branches. prove., Q. Prove the hypothes...

Q. Prove the hypothesis that "A tree having 'm' nodes has exactly (m-1) branches".      Ans: A tree having m number of nodes has exactly (m-1) branches Proof: A root

Disadvantages of the lifo costing method, The disadvantages or limitations ...

The disadvantages or limitations of the last in first out costing method are: The election of last in first out for income tax purposes is binding for all subsequent yea

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