Counting sort

Algorithms Counting sort

As we learned from the article A lower approximation of the sorting problem complexity we cannot sort with a better time complexity than O(n log n). This limitation applies to the decision tree, which must be covered by mutual comparison of the items. However, what if we could sort the items without comparing them? Would we be able to sort the array in linear time? It sounds crazy, but it's totally possible. There are multiple sorting algorithms based on this principle and Counting sort is one of them.

This algorithm only sorts integers, which isn't necessarily a problem because it's what we usually sort. For other values, we can simply convert the data into integers (e.g. multiply the numbers with 2 decimal places by one hundred, sort them, and then divide them again). The sorting part is done using an auxiliary array which is called the counting array, sometimes also the indexing array. The counting array should be as long as


 

...End of the preview...

Premium article

Premium article

ict.social is a large database made up of manuals and tutorials, whose main goal is to provide high-quality IT education to everyone. We started out in the Czech republic, where we display roughly a million articles per month and receive plenty of gratitude from our users. Thanks to our successful establishment, we are now bringing these articles to the rest of the world.

Although we are trying to keep our content free of charge, maintaining the site is a huge effort for everyone involved. Therefore, some content (exercises and more advanced material) costs network points. Don't worry, they're really cheap :)

Article description

Requested article covers this content:

This article is about Counting sort, which is able to sort numbers according to their value in linear time. Source codes for languages Java,C#,Delphi,Ruby.
To access the article, you need 10 points
Currently, you have 0 points
You gain 10 points for adding an article to the site, or for $0.90

Buying this article gives you unlimited access to it forever. You will learn some more and help us keep giving our site maintenance which helps you and others get better futures. It's a win-win.

This article is licensed :Premium, by buying this article, you agree with the terms of use.

You gain points by supporting our network. This is done by sending a helpful amount of money to support the site, or by creating content for the network.

You can get points immediately using:

Credit card SMS Wire transfer
Credit card SMS Wire transfer

 

Article has been written for you by David Jancik
Avatar
.
Thumbnail
Previous article
Quicksort
Thumbnail
All articles in this section
Algorithms
Activities (2)