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

Delete a given specific node from a doubly linked list. , D elete a specif...

D elete a specific Node from Double Linked List as follows DELETEDBL(INFO, FORW, BACK, START, AVAIL,LOC) 1. [Delete Node] Set FORW [ BACK [LOC]]:= FORW[LOC]& BACK [FORW[

Data searching, In file access: what is the difference between serial, seq...

In file access: what is the difference between serial, sequential and indexed sequential searching

Explain Hashing, What do you mean by hashing? Hashing gives the direct ...

What do you mean by hashing? Hashing gives the direct access of record from the file no matter where the record is in the file. This is possible with the help of a hashing func

Difference in grounded header and circular header Link List, Q. State the d...

Q. State the difference between a grounded header link list and a circular header link list?     Ans: A header linked list is a linked list which all the time c

Define dynamic programming, Define Dynamic Programming  Dynamic  progra...

Define Dynamic Programming  Dynamic  programming  is  a  method  for  solving  problems  with  overlapping  problems.  Typically, these sub problems arise from a recurrence rel

Depth of complete binary tree, What will be depth do , of complete binary t...

What will be depth do , of complete binary tree of n nodes, where nodes are labelled from 1 to n with root as node and last leaf node as node n

Comparisions and assignments in worst case, Q. Calculate that how many key ...

Q. Calculate that how many key comparisons and assignments an insertion sort makes in its worst case?        Ans: The worst case performance occurs in insertion

Representation of max-heap sequentially, Q. How do we represent a max-heap ...

Q. How do we represent a max-heap sequentially? Explain by taking a valid   example.         Ans: A max heap is also called as a descending heap, of size n is an almos

Algorithmss, calculate gpa using an algorithm

calculate gpa using an algorithm

Sorting, compare and contrast the bubble sort,quick sort,merge sort and rad...

compare and contrast the bubble sort,quick sort,merge sort and radix sort

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