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

Implement a min-heap, Description A heap is an efficient tree-based data...

Description A heap is an efficient tree-based data structure that can be used as a priority queue. Recall that the abstract data type of a priority queue has the following opera

Define a sparse metrics, Define a sparse metrics. A matrix in which num...

Define a sparse metrics. A matrix in which number of zero entries are much higher than the number of non zero entries is known as sparse matrix. The natural method of showing m

Frequency count, what is frequency count with examble

what is frequency count with examble

Definition of algorithm, Definition of Algorithm Algorithm must have th...

Definition of Algorithm Algorithm must have the following five characteristic features: 1.      Input 2.      Output 3.      Definiteness 4.      Effectiveness 5

Algorithm, Ask question #MWhich of the following is not a characteristic of...

Ask question #MWhich of the following is not a characteristic of good algorithm? inimum 100 words accepted#

Header linked list, creation,insertion,deletion of header linked list using...

creation,insertion,deletion of header linked list using c.

C++, 7. String manipulation 7.a Write a C Program using following strin...

7. String manipulation 7.a Write a C Program using following string manipulation functions a) strcpy b) strncpy c) strcmp d) strncmp e) strlen f) strcat

List various problem solving techniques, List various problem solving techn...

List various problem solving techniques. There are two techniques:- 1.  Top down 2.  Bottom- up

Red black tree, red black tree construction for 4,5,6,7,8,9

red black tree construction for 4,5,6,7,8,9

Which is the most suitable data type, Problem 1. You are asked to store...

Problem 1. You are asked to store Names of all 100 students of class A in your Learning Centre. Which data type will you use? What is its syntax? Explaining the data typ

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