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

The threaded binary tree, By changing the NULL lines in a binary tree to th...

By changing the NULL lines in a binary tree to the special links called threads, it is possible to execute traversal, insertion and deletion without using either a stack or recursi

Define abstract data type & column major ordering for arrays, Q1. Define th...

Q1. Define the following terms: (i) Abstract data type. (ii) Column major ordering for arrays. (iii)  Row major ordering for arrays. Q2. Explain the following: (i) A

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

File organization, Define File organization''s and it''s types

Define File organization''s and it''s types

Estimate cost of an optimal diapath, Normally a potential y satisfies y r ...

Normally a potential y satisfies y r = 0 and 0 ³ y w - c vw -y v . Given an integer K³0, define a K-potential to be an array y that satisfies yr = 0 and K ³ y w - c vw -y v

Graph traversal schemes, Various graph traversal schemes Graph Traversa...

Various graph traversal schemes Graph Traversal Scheme. In many problems we wish to investigate all the vertices in a graph in some systematic order. In graph we often do no

Total impedent of the circuit, an electrical student designed a circuit in...

an electrical student designed a circuit in which the impedence in one part of a series circuit is 2+j8 ohms and the impedent is another part of the circuit is 4-j60 ohm mm program

Example of back face detection method, Example of Back Face Detection Metho...

Example of Back Face Detection Method To illustrate the method, we shall start with the tetrahedron (pyramid) PQRS of     Figure with vertices P (1, 1, 2), Q (3, 2, 3), R (1,

Applications of binary trees, In computer programming, Trees are utilized ...

In computer programming, Trees are utilized enormously. These can be utilized for developing database search times (binary search trees, AVL trees, 2-3 trees, red-black trees), Gam

The various ways in which lc code can be accessed, Problem Your LC code...

Problem Your LC code is stored in a memory location as shown and the variable name is LC                  LC Memory address       Content(LC code)

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