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

Define min-heap, Define min-heap A min-heap is a complete binary tree i...

Define min-heap A min-heap is a complete binary tree in which each element is less than or equal to its children. All the principal properties of heaps remain valid for min-hea

Inorder and preorder traversal to reconstruct a binary tree, Q. Using the f...

Q. Using the following given inorder and preorder traversal reconstruct a binary tree Inorder sequence is D, G, B, H, E, A, F, I, C

Stacks, Q. Explain w hat are the stacks? How can we use the stacks to chec...

Q. Explain w hat are the stacks? How can we use the stacks to check whether an expression is correctly parentheses or not. For example (()) is well formed but (() or )()( is not w

Explain in brief the asymptotic notations, Question 1 Write the different ...

Question 1 Write the different characteristics of an algorithm Question 2 Explain in brief the asymptotic notations Question 3 Write an algorithm of insertion sort and e

Dqueue, how can i delete from deque while deletion is restricted from one e...

how can i delete from deque while deletion is restricted from one end

Name the four data type groups, There are four data type groups: I...

There are four data type groups: Integer kepts whole numbers and signed numbers Floating-point Stores real numbers (fractional values). Perfect for storing bank deposit

Exlain double linked list, Double Linked List In a doubly linked list, ...

Double Linked List In a doubly linked list, also known as 2 way lists, each node is separated into 3 parts. The first part is called last pointer field. It has the address of t

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

Compare two functions, Comp are two functions n 2 and 2 n / 4...

Comp are two functions n 2 and 2 n / 4 for distinct values of n. Determine When s ec on d function b ec om es l a r g er th an f i r st functi

Design a binary search tree, Binary Search Tree usage: Write a progra...

Binary Search Tree usage: Write a program to compare the time taken for a search in a skewed tree, a balanced tree, and a random tree. Specically, your program should do the

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages