Searching & Sorting

1. Searching & Sorting

2. Linear Search • I'm thinking of a number between 1 and 100 • You try to guess it • I'll give too low/too high hints

3. Linear Search • I'm thinking of a number between 1 and 100 • You try to guess it • I'll give too low/too high hints • Method #1 – Linear Search • 1, 2, 3….

4. Binary Search • Method #2 – Binary Search • Pick middle of remaining search space • Too high? Eliminate middle and above • Too low? Eliminate middle and below

5. Algorithm

6. Binary Search Searching for 5:

7. Binary Search Searching for 5:

8. Binary Search Searching for 5:

9. Binary Search Searching for 5:

10. Binary Search Searching for 5:

11. Binary Search Searching for 5:

12. Binary Search Searching for 6:

13. Binary Search Searching for 6:

14. Binary Search Searching for 6:

15. Binary Search Searching for 6:

16. Binary Search Searching for 6:

17. Binary Search Searching for 6:

18. Basic Sorts

19. Simple Sort • Get a list of unsorted numbers • Make a new empty list • Repeat steps these steps until the unsorted list is empty • Select the smallest unsorted number • Move this number to the sorted list

20. Insertion Sort • Get a list of unsorted numbers • Set a marker for the sorted section after the first number in the list • Repeat steps until the unsorted section is empty • Select the first unsorted number • Swap this number to the left until it arrives at the correct sorted position • Advance the sorted marker to the right one position

21. Selection Sort • Get a list of unsorted numbers • Set a marker for the sorted section at the front of the list • Repeat steps until one number remains in the unsorted section • Find smallest number in the unsorted section • Swap this number with the first number in the unsorted section • Advance the marker to the right one position