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

Stack, implement multiple stacks ina single dimensional array. write algori...

implement multiple stacks ina single dimensional array. write algorithams for various stack operation for them.

Graph with n vertices will absolutely have a parallel edge, A graph with n ...

A graph with n vertices will absolutely have a parallel edge or self loop if the total number of edges is greater than n-1

State the term access restrictions - container, What is Access Restriction...

What is Access Restrictions Structured containers with access restrictions only allow clients to add, remove and examine elements at certain locations in their structure. For

Algorithms, write short note on algorithms

write short note on algorithms

What is the best case complexity of quick sort, What is the best case compl...

What is the best case complexity of quick sort In the best case complexity, the pivot is in the middle.

Binary tree with depth 3, Q. Construct a complete binary tree with depth 3 ...

Q. Construct a complete binary tree with depth 3 for this tree which is maintained in the memory using the linked representation. Make the adjacency list and adjacency matrix for t

Hashing, what is hashing? what are diffrent method of hashing?

what is hashing? what are diffrent method of hashing?

Create algorithm for similarities between documents, Here is a diagram show...

Here is a diagram showing similarities between documents; this is an actual set of physics lab assignments from a large university. Each node (square) in the graph is a doc

Dataset for dmi, The following DNA sequences are extracted from promoter re...

The following DNA sequences are extracted from promoter region of genes which are co-regulated by the same transcription factor (TF). The nucleotide segments capitalized in the giv

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