Quicksort is a sorting algorithm that selects an item and rearranges the array forming two partitions so that all items below the item come before and all items above come after. The algorithm is then used recursively to the parts until it gets a sorted list. In this article, I’ll walk you through how to implement the quicksort algorithm using Python.

## Quicksort Algorithm

The quicksort algorithm chooses an element which is usually the last element in the array. The algorithm maintains the index to place the element in a variable whenever it finds an element less than or equal to the element, this index is incremented and this element would be placed before the element.

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The advantages of using the quick sorting algorithm are that on average it runs very fast same as the merge sort algorithm and does not require additional memory. The disadvantages of this sorting algorithm are that its running time can differ depending on the elements of the array. It is not very stable also, and its running time may decrease if the input array is almost sorted.

## Quicksort Algorithm using Python

Now let’s see how to implement the quick sorting technique by using the Python programming language:

Output:

[1, 2, 3, 3, 5, 6, 6, 8, 9]

### Summary

Sorting algorithms are the most important concept for someone who is learning a programming language. It doesn’t matter what aspect of programming interests you like you may be doing programming for machine learning, robotics, software development, web development or any other domain, the use of sorting algorithms are everywhere.

I hope you liked this article on the implementation of the quicksort algorithm using Python programming language. Feel free to ask your valuable questions in the comments section below.