Java Quicksort is thought to be the fastest sorting algorithm. The time complexity in quicksort is O(n log n) for the best and average case and O(n^2) in the bad case. And as the time complexity is the biggest thing that should be kept in the mind, so we always preferred quicksort in many cases among any other sorting algorithm.

Java QuickSort Example

QuickSort is the Divide and Conquer algorithm. It picks an item as a pivot element and partitions the given array around the selected pivot. There are many different versions of the quickSort that pick pivot in different ways.

1. Always pick the first element as a pivot.
2. Always pick the last item as the pivot (implemented below)
3. Pick a random item as the pivot.
4. Pick median as the pivot.

The key process in quickSort is a partition(). The target of partitions is, given an array and an element x of an array as the pivot, put x at its correct position in a sorted array and put all smaller elements (smaller than x) before x, and put all greater items (greater than x) after x. All this should be done in linear time.

#java #quicksort