Bubble Sort Algorithm

// Bubble sort algorithm in increasing order:

1. public class BubbleSortAlgorithm {
2. 
   
3. public static void main(String[] args) {
4. int a[] = { 3, 4, 5, 43, 2, 2, 45, 66, 5, 4, 32 };
5. int temp;
6. 
   
7. for (int i = 0; i < a.length; i++) {
8. for (int j = 0; j < a.length-1; j++) {
9. if (a[j] > a[j + 1]) {
10. temp = a[j];
11. a[j] = a[j + 1];
12. a[j + 1] = temp;
13. }
14. }
15. }
16. for (int i : a) {
17. System.out.print(i + " ");
18. }
19. }
20. }

Ouput: 2 2 3 4 4 5 5 32 43 45 66
Average time complexity: O(n²)

// Bubble sort algorithm in decreasing order:

1. public class BubbleSortAlgorithm {
2. 
   
3. public static void main(String[] args) {
4. int a[] = { 3, 4, 5, 43, 2, 2, 45, 66, 5, 4, 32 };
5. int temp;
6. 
   
7. for (int i = 0; i < a.length; i++) {
8. for (int j = 0; j < a.length-1; j++) {
9. if (a[j] < a[j + 1]) {
10. temp = a[j];
11. a[j] = a[j + 1];
12. a[j + 1] = temp;
13. }
14. }
15. }
16. for (int i : a) {
17. System.out.print(i + " ");
18. }
19. }
20. }

Output: 66 45 43 32 5 5 4 4 3 2 2 
Average time complexity: O(n²)

// II Method: Increasing order

1. public class BubbleSort{
2. 
   
3. public static void main(String[] args) {
4. 
   
5. int arr[] = { 5, 6, 4, 3, 3, 5, 6, 9, 8 };
6. for (int i = 0; i < arr.length; i++) {
7. for (int j = 0; j < arr.length; j++) {
8. if (arr[i] < arr[j]) {
9. int temp = arr[i];
10. arr[i] = arr[j];
11. arr[j] = temp;
12. }
13. }
14. }
15. for (int i : arr)
16. System.out.print(i + " ");
17. }
18. }

Output: 3 3 4 5 5 6 6 8 9
Average time complexity: O(n²)

Bubble sort in decreasing order:

1. public class BubbleSort {
2. 
   
3. public static void main(String[] args) {
4. 
   
5. int arr[] = { 5, 6, 4, 3, 3, 5, 6, 9, 8 };
6. for (int i = 0; i < arr.length; i++) {
7. for (int j = 0; j < arr.length; j++) {
8. if (arr[i] > arr[j]) {
9. int temp = arr[i];
10. arr[i] = arr[j];
11. arr[j] = temp;
12. }
13. }
14. }
15. for (int i : arr)
16. System.out.print(i + " ");
17. }
18. }

Output: 9 8 6 6 5 5 4 3 3
Average time complexity: O(n²)