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

Tree traversal, Q. What do you understand by the tree traversal? Write down...

Q. What do you understand by the tree traversal? Write down the procedure for traversing a binary tree in preorder and execute it on the following tree.    Ans: Th

Sort 5, The number of interchanges needed to sort 5, 1, 6, 2 4 in ascending...

The number of interchanges needed to sort 5, 1, 6, 2 4 in ascending order using Bubble Sort is 5

Depth first search, DEPTH FIRST SEARCH (DFS) The approach adopted into ...

DEPTH FIRST SEARCH (DFS) The approach adopted into depth first search is to search deeper whenever possible. This algorithm frequently searches deeper through visiting unvisite

Algorithm.., write an algorithm to sort given numbers in ascending order us...

write an algorithm to sort given numbers in ascending order using bubble sort

Algorithm for similar binary tree, Q. The two Binary Trees are said to be s...

Q. The two Binary Trees are said to be similar if they are both empty or if they are both non- empty and left and right sub trees are similar. Write down an algorithm to determine

Design and test a reference array, Instructions Design and test a r...

Instructions Design and test a reference array. Reference array stores the references to user supplied objects of different types. Just think it as a heterogeneous array wh

Write procedure to the insert a node into the linked list, Q. Write a proce...

Q. Write a procedure to the insert a node into the linked list at a particular position and draw the same by taking an example?

Parallel implementation of the raytracer, You are supposed to do the follow...

You are supposed to do the following: Write a parallel implementation of the raytracer using pthreads. Measure and compare the execution times for (i) the sequential ver

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