Selection Sort, Insertion Sort, Bubble Sort Main idea: find the smallest element put it in the first position find the next smallest element put it in the second position

1. Class No.38 Data Structures http://ecomputernotes.com

2. Sorting http://ecomputernotes.com

3. Sorting Integers 20 8 5 10 7 5 7 8 10 20 How to sort the integers in this array? http://ecomputernotes.com

6. Selection Sort -- Example 19 12 7 5 http://ecomputernotes.com 1 2 3 0 7 12 19 5 a: 1 2 3 0 7 19 12 5 a: 1 2 3 0 19 7 12 5 a: 1 2 3 0 7 12 19 5 a: 1 2 3 0 5 7 12 19 a: a: 1 2 3 0

9. Swap Action (SelectionSorting) http://ecomputernotes.com 5 8 20 10 7 5 7 20 10 8 5 7 8 10 20 20 8 5 10 7 5 7 8 10 20

12. Insertion Sort -- Example http://ecomputernotes.com 1 2 3 0 12 5 7 19 a : 1 2 3 0 19 5 7 12 a : 1 2 3 0 12 19 7 5 a : 1 2 3 0 7 12 19 5 a :

14. Insertion Sort -- animation count val pos 1 12 0 1 12 -1 19 12 http://ecomputernotes.com 1 2 3 0 12 5 7 19 a : 1 2 3 0 19 5 7 19 a : 1 2 3 0 5 7 19 a : 12 1 2 3 0 19 5 7 12 a :

15. Insertion Sort -- animation (cont) count val pos 2 5 1 2 5 -1 19 12 2 5 0 5 http://ecomputernotes.com 1 2 3 0 12 19 7 5 a : 1 2 3 0 19 5 7 12 a : 1 2 3 0 5 7 12 a : 19 1 2 3 0 19 7 12 a : 19 1 2 3 0 12 19 7 12 a :

16. Insertion Sort -- animation (cont) count val pos 3 7 2 3 7 0 3 7 1 19 12 7 http://ecomputernotes.com 1 2 3 0 12 19 7 5 a : 1 2 3 0 12 19 7 5 a : 1 2 3 0 12 19 19 5 a : 1 2 3 0 12 12 19 5 a : 1 2 3 0 7 12 19 5 a :

19. Bubble Sort -- Example a: http://ecomputernotes.com 1 2 3 0 12 7 19 5 a: 1 2 3 0 12 7 19 5 a: 19 12 7 5 1 2 3 0 a: 12 19 7 5 a: 1 2 3 0 5 12 7 19 1 2 3 0 a: 1 2 3 0 12 7 19 5 a: 1 2 3 0 7 12 19 5 a: 1 2 3 0 7 12 19 5 a: 1 2 3 0 7 12 19 5 a: 1 2 3 0 7 12 19 5 a:

24. Divide and Conquer What if we split the list into two parts? 10 12 8 4 2 11 7 5 http://ecomputernotes.com 10 12 8 4 2 11 7 5

25. Divide and Conquer Sort the two parts: http://ecomputernotes.com 10 12 8 4 2 11 7 5 4 8 10 12 2 5 7 11

26. Divide and Conquer Then merge the two parts together: http://ecomputernotes.com 4 8 10 12 2 5 7 11 2 4 5 7 8 10 11 12