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

Write a program to create a heap file, Write a program to create a heap fil...

Write a program to create a heap file that holds the records in the file " data_2013 " The source records are variablelength.However, the heap file should hold fixed-length reco

Algorithm to build a binary tree , Q. Give the algorithm to build a binary ...

Q. Give the algorithm to build a binary tree where the yields of preorder and post order traversal are given to us.

Merge sorting, ESO207: Programming Assignment 1 Due on 6 Sept, 2015. To be ...

ESO207: Programming Assignment 1 Due on 6 Sept, 2015. To be submitted online. Problem In this assignment you are required to implement k-way Merge Sort algorithm. In this version p

Multiple stack, implement multiple stack in single dimensionl array.write a...

implement multiple stack in single dimensionl array.write algorithms for various stack operation for them

Boar corloring, Board coloring , C/C++ Programming

Board coloring , C/C++ Programming

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

Dijkstras algorithm, Djikstra's algorithm (named after it is discovered by ...

Djikstra's algorithm (named after it is discovered by Dutch computer scientist E.W. Dijkstra) resolves the problem of finding the shortest path through a point in a graph (the sour

Tree structure, We would like to implement a 2-4Tree containing distinct in...

We would like to implement a 2-4Tree containing distinct integer keys. This 2-4Tree is defined by the ArrayList Nodes of all the 2-4Nodes in the tree and the special 2-4Node Root w

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