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

Applications, Arrays are simple, however reliable to employ in more conditi...

Arrays are simple, however reliable to employ in more condition than you can count. Arrays are utilized in those problems while the number of items to be solved out is fixed. They

Brute force, Determine the number of character comparisons made by the brut...

Determine the number of character comparisons made by the brute-force algorithm in searching for the pattern GANDHI in the text

Depth first traversal, A depth-first traversal of a tree visits a nodefirst...

A depth-first traversal of a tree visits a nodefirst and then recursively visits the subtrees of that node. Similarly, depth-first traversal of a graph visits a vertex and then rec

Different ways for representing s graph, W h at are the different ways by...

W h at are the different ways by which we can represent graph?  Represent the graph drawn below using those ways.     T he d iff e r e nt w a y s by

What is assertions and abstract data types, Assertions and Abstract Data Ty...

Assertions and Abstract Data Types Even though we have defined assertions in terms of programs, notion can be extended to abstract data types (which are mathematical entities).

Define minimum spanning tree, Define Minimum Spanning Tree A minimum sp...

Define Minimum Spanning Tree A minimum spanning tree of a weighted linked graph is its spanning tree of the smallest weight, where the weight of a tree is explained as the sum

Traversing a graph, two standards ways of traversing a graph in data struc...

two standards ways of traversing a graph in data structure

Ruby implements range of t abstract data type, Ruby implements Range of T A...

Ruby implements Range of T Abstract data type Ruby implements Range of T ADT in its Range class. Elements of carrier set are represented in Range instances by recording interna

Find a minimum cost spanning arborescence rooted, Find a minimum cost spann...

Find a minimum cost spanning arborescence rooted at r for the digraph shown below, using the final algorithm shown in class. Please show your work, and also give a final diagram wh

Give example of assertion and abstract data type, Give example of assertion...

Give example of assertion and abstract data type For illustration, consider Natural ADT whose carrier set is the set of non-negative integers and whose operations are the usual

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