Complexity of an algorithm, Data Structure & Algorithms

Assignment Help:

Q. Explain the complexity of an algorithm?  What are the worst case analysis and best case analysis explain with an example.                                                                                                                

Ans:

The complexity of the algorithm M is the function f(n) which gives the running time or storage space requirement of the algorithm in terms of the size n of the input data. Frequently, the storage space needed by an algorithm is just a multiple of the data size n. Therefore, the term "complexity" should be referring to the running time of the algorithm.

We find the complexity function f(n) for the certain number of cases. The two cases to which one usually investigates in complexity theory are as follows:-
i. The worst case:-  the maximum value of f(n) for any input possible
ii. The best case:-  the least possible value of f(n)

For example:-

Hear if we take an example of linear search in which an integer Item is to searched or found in an array Data. The complexity if the search algorithm is given by number C of comparisons between Item and Data[k].

Worst case:-

The worst case occurs when the Item is last element in the array Data or is it not there at all. In both of these cases, we get

C(n)=n

In the average case, we presume that the Item is present is the array and is likely to be present in any position in the array. Hence the number of comparisons can be any of the numbers 1, 2, 3........n and each number occurs with probability

p = 1/n.

C(n) = 1. 1/n + 2.1/n + ... + n.1/n

= (n+1) / 2

hence the average number of comparisons needed to locate the Item in to array Data is approximately the same to half the number of elements in the Data list.


Related Discussions:- Complexity of an algorithm

Objectives of lists, After going through this unit, you will be able to: ...

After going through this unit, you will be able to: • define and declare Lists; • understand the terminology of Singly linked lists; • understand the terminology of Doubly

Use of asymptotic notation in the study of algorithm, Q. What is the need o...

Q. What is the need of using asymptotic notation in the study of algorithm? Describe the commonly used asymptotic notations and also give their significance.

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

Creation of doubly linked list, Program: Creation of Doubly Linked List ...

Program: Creation of Doubly Linked List OUTPUT Input the values of the element -1111 to come out : 1 Input the values of the element -1111 to come out : 2 Inpu

Interest, I=PR/12 numbers of years : Interest Rate up to 1 years : 5...

I=PR/12 numbers of years : Interest Rate up to 1 years : 5.50 Up to 5 years : 6.50 More than 5 year : 6.75 please design an algorithm based on the above information

Booth algorithm, what is boot algorithm and some example

what is boot algorithm and some example

B-TREE and AVL tree diffrance, Explain process of B-TREE and what differen...

Explain process of B-TREE and what difference between AVL Tree Using Algorithms

What are circular queues, What are circular queues?  Circular queue: St...

What are circular queues?  Circular queue: Static queues have a very large drawback that once the queue is FULL, even though we erase few elements from the "front" and relieve

Explain merge sort, Question 1 Explain the use of algorithms in computing ...

Question 1 Explain the use of algorithms in computing Question 2 Explain time complexity and space complexity of an algorithm Question 3 Explain how you can analyz

Acyclic graphs, Acyclic Graphs In a directed graph a path is said to fo...

Acyclic Graphs In a directed graph a path is said to form a cycle is there exists a path (A,B,C,.....P) such that A = P. A graph is called acyclic graph if there is no cycle in

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