Bubble sort algorithm is the most famous sorting algorithm as it is studied in schools, universities and various computer courses.
The idea of the algorithm is as follows:
- we iterate through the array and swap adjacent elements pair by pair if they aren’t in the required order.
- each iteration through the array pushes one item (“bubble”) to the outermost position.
The main weak point of this approach: the time complexity is O(n2).
This algorithm is created for educational purposes only: never use it in production code!
import java.util.Arrays;
public class ImplementBubbleSort {
// An optimized version of Bubble Sort
private static void bubbleSort(int[] arr, int n)
{
int buffer;
boolean swapped;
for (var i = 0; i < n - 1; i++) {
swapped = false;
for (var j = 0; j < n - i - 1; j++) {
if (arr[j] > arr[j + 1]) {
buffer = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = buffer;
swapped = true;
}
}
if (!swapped)
break;
}
}
public static void main(String[] args)
{
var array = new int[] { 64, 34, 25, 12, 22, 11, 90 };
var n = array.length;
bubbleSort(array, n);
System.out.println("Sorted array: ");
System.out.println(Arrays.toString(array));
}
}