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

Surrounding of sub division method, Surrounding of sub division method ...

Surrounding of sub division method A polygon surrounds a viewport if it completely encloses or covers the viewport. This happens if none of its sides cuts any edge of the viewp

How can a lock object be called in the transaction, How can a lock object b...

How can a lock object be called in the transaction? By calling Enqueue and Dequeue in the transaction.

Bubble sort, In this sorting algorithm, multiple swapping occurs in one pas...

In this sorting algorithm, multiple swapping occurs in one pass. Smaller elements move or 'bubble' up to the top of the list, so the name given to the algorithm. In this method,

Define the term array, Define the term array. An array is a way to refe...

Define the term array. An array is a way to reference a series of memory locations using the same name. Each memory location is represented by an array element. An  array eleme

Frequency count, what is frequency count with examble

what is frequency count with examble

Convertion, how we can convert a graph into tree

how we can convert a graph into tree

Illustrate the wire frame representation, RENDERING, SHADING AND COLOURING ...

RENDERING, SHADING AND COLOURING By introducing hidden line removal we have already taken one step away from wire-frame drawings towards being able to realistically model and d

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

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