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

Adjacency list representation, Adjacency list representation An Adjacen...

Adjacency list representation An Adjacency list representation of Graph G = {V, E} contains an array of adjacency lists mentioned by adj of V list. For each of the vertex u?V,

Tree, application of threaded binary treee

application of threaded binary treee

Linked list implementation of a dequeue, Double ended queues are implemente...

Double ended queues are implemented along doubly linked lists. A doubly link list can traverse in both of the directions as it contain two pointers namely left pointers and righ

Merging, Merging two sequence using CREW merge

Merging two sequence using CREW merge

Algorithm that inputs the codes for all items in stock, A shop sells books,...

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

Amortized algorithm analysis, In the amortized analysis, the time needed to...

In the amortized analysis, the time needed to perform a set of operations is the average of all operations performed. Amortized analysis considers as a long sequence of operations

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

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

Data Mining and Neural Networks, I am looking for some help with a data min...

I am looking for some help with a data mining class with questions that are about neural networks and decision trees. Can you help? I can send document with questions.

Heights of 500 students `Algorithms`, Write an algorithm, using a flowchart...

Write an algorithm, using a flowchart, which inputs the heights of all 500 students and outputs the height of the tallest person and the shortest p erson in the school.

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