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

Execute algorithm to convert infix into post fix expression, Q. Execute you...

Q. Execute your algorithm to convert the infix expression to the post fix expression with the given infix expression as input Q = [(A + B)/(C + D) ↑ (E / F)]+ (G + H)/ I

What is quick sort, What is quick sort?   Answer Quick sort is on...

What is quick sort?   Answer Quick sort is one of the fastest sorting algorithm used for sorting a list. A pivot point is chosen. Remaining elements are divided or portio

Define rule-based expert system, 1. Define the following terms in a rule-ba...

1. Define the following terms in a rule-based expert system? a) Knowledge base b) Inference engine 2. What is a fuzzy rule? Explain the difference between classical and fuzzy

Curve, write a c++ program to find out the area of a curve y=f(x) between x...

write a c++ program to find out the area of a curve y=f(x) between x=a and x=b

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

State a algorithm that inputs the heights of all 500 student, As part of an...

As part of an experiment, a school measured heights (in metres) of all its 500 students. Write an algorithm, using a flowchart that inputs the heights of all 500 students and ou

Multilist file organisation, what is multilist length file organisation? ex...

what is multilist length file organisation? explain with an example

Define game trees, Game trees An interesting application of trees is th...

Game trees An interesting application of trees is the playing of games such as tie-tac-toe, chess, nim, kalam, chess, go etc. We can picture the sequence of possible moves by m

Sorting, explain quick sort algorithm

explain quick sort algorithm

Chaining Method as Method of Collision Resolution , Q. The given values are...

Q. The given values are to be stored in a hash table 25, 42, 96, 101, 102, 162, 197 Explain how the values are hashed by using division technique of hashing with a table

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