1. Alg2_1c Extra Material for Alg2_1
Algorithms part2
Alg2_1c
Extra Material for Alg2_1

2. Bubble Sort
Algorithm
Define the entire array as the unsorted portion of the array.
While the unsorted portion of the array has more than one element:
1. For every element in the unsorted portion, swap with the next neighbor if it is larger than the neighbor.
2. Reduce the size of the unsorted portion of the array by 1.

3. 14 2 10 5 1 3 17 7

4. Bubble sort code
public void bubbleSort(int[] arr) { boolean swapped = true; int j = 0; int tmp; while (swapped) { swapped = false; j++; for (int i = 0; i < arr.length - j; i++) { if (arr[i] > arr[i + 1]) { tmp = arr[i]; arr[i] = arr[i + 1]; arr[i + 1] = tmp; swapped = true; } } } }

5. Bubble Sort – Algorithm Complexity
Time consuming operations
compares, swaps.
#Compares
a for loop embedded inside a while loop
(n-1)+(n-2)+(n-3) …+1 , or O(n2)
#Swaps
inside a conditional -> #swaps data dependent !!
Best Case 0, or O(1)
Worst Case (n-1)+(n-2)+(n-3) …+1 , or O(n2)

6. Remember: Sorting Algorithms
Insertion Sort
O( n2 )
Selection Sort
Bubble Sort