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

Sorting, Sort the following array of elements using quick sort: 3, 1, 4, 1,...

Sort the following array of elements using quick sort: 3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8.

FIRST function in the compiler construction, I need a recursive algorithm t...

I need a recursive algorithm to implement the FIRST function to any grammar

Determine yiq colour model, Determine YIQ Colour Model Whereas an RGB m...

Determine YIQ Colour Model Whereas an RGB monitor requires separate signals for the red, green, and blue components of an image, a television monitor uses a single composite si

Implement an open hash table, In a chained hash table, each table entry is ...

In a chained hash table, each table entry is a pointer to a collection of elements. It can be any collection that supports insert, remove, and find, but is commonly a linked list.

Siso-4bit register, explain working of siso-register to store 1011 and show...

explain working of siso-register to store 1011 and show timing diagram &table

Complete trees, This is a k-ary position tree wherein all levels are filled...

This is a k-ary position tree wherein all levels are filled from left to right. There are a number of specialized trees. They are binary trees, AVL-trees, binary search trees, 2

What is gouraud shading, Gouraud Shading The faceted appearance of a La...

Gouraud Shading The faceted appearance of a Lambert shaded model is due to each polygon having only a single colour. To avoid this effect, it is necessary to vary the colour ac

Implementation of queue, For a queue a physical analogy is a line at bookin...

For a queue a physical analogy is a line at booking counter. At booking counter, customers go to the rear (end) of the line & customers are attended to several services from the fr

A binary tree in which levels except possibly the last, A binary tree in wh...

A binary tree in which if all its levels except possibly the last, have the maximum number of nodes and all the nodes at the last level appear as far left as possible, is called as

Non-recursive implementation of binary tree traversals, As we have seen, as...

As we have seen, as the traversal mechanisms were intrinsically recursive, the implementation was also easy through a recursive procedure. Though, in the case of a non-recursive me

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