Complexity of quick sort, Data Structure & Algorithms

Assignment Help:

Q. What do you mean by the best case complexity of quick sort and outline why it is so. How would its worst case behaviour arise?                                                                                                 

Ans:

In the best case complexity, pivot is in the middle. To simplify the calculation, we assume that the two sub-files are both  exactly half  of the size of the original file, and although this gives a minor overestimate, this is except able because we are only interested in a Big-Oh answer.

T(n) = 2T(n/2) + cn

which yields

T(n) = cn log n + n = O(n log n)

In the worst case the pivot is the smallest element, all the time. Then i = 0 and if we ignore  T(0) = 1, which is not important, the recurrence is T(n) = T(n - 1) + cn, n > 1 which yields

1908_Quick Sort1.png


Related Discussions:- Complexity of quick sort

Stack, infix to revrse polish

infix to revrse polish

Determine the class invariants- ruby, Determine the class invariants- Ruby ...

Determine the class invariants- Ruby Ruby has many predefined exceptions classes (like ArgumentError) and new ones can be created easily by sub-classing StandardError, so it's

Example of telephone directory, A telephone directory having n = 10 records...

A telephone directory having n = 10 records and Name field as key. Let us assume that the names are stored in array 'm' i.e. m(0) to m(9) and the search has to be made for name "X"

What is bubble sort, What is bubble sort? Bubble Sort: The basic ide...

What is bubble sort? Bubble Sort: The basic idea in bubble sort is to scan the array to be sorted sequentially various times. Every pass puts the largest element in its corr

Define container in terms of object-oriented terms, Define container in te...

Define container in terms of  object-oriented terms A Container is a broad category whose instances are all more specific things; there is never anything which is just a Contai

Data structure- tree, Tree is dynamic data structures. Trees can expand & c...

Tree is dynamic data structures. Trees can expand & contract as the program executes and are implemented via pointers. A tree deallocates memory whereas an element is deleted.

Find the optimal solution - branch and bound algorithm, Consider the follow...

Consider the following 5-city traveling salesman problem. The distance between each city (in miles) is shown in the following table: (a) Formulate an IP whose solution will

Memory allocation strategies, Q. Explain the various memory allocation stra...

Q. Explain the various memory allocation strategies.                                                            Ans. M e m ory Allocation Strategies are given as follow

Unification algorithm, i want to write code for unification algorithm with ...

i want to write code for unification algorithm with for pattern matching between two expression with out representing an expression as alist

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

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