Assist.Prof. Dr. Nükhet ÖZBEK Ege University Department of Electrical&Electronics Engineering

1. Introduction to Computing Lecture 00: Part 3Introduction to Algorithms and Flowcharts (continued) • Assist.Prof.Dr. NükhetÖZBEK • Ege University • Department of Electrical&Electronics Engineering • nukhet.ozbek@ege.edu.tr

2. Expressing Algorithms • Natural Languages • Pseudocode • Flowcharts • Programming Languages

3. Natural Language Algorithm Cilbir • 6 eggs • ½ kg yogurt • 3 large garlic cloves • 4 Tbs fresh butter • 1 tsp red pepper, coarsely ground • 2 middle-sized onions cut horizontally • plenty water • Boil water in a fairly big pot. Break one by one the eggs and pour them in a plate, being careful not to break the yolk. To ensure a homogenous cooking, let them “glide” from the plate into the boiling water. Within three minutes the eggs are ready but if you prefer hard-boiled, allow them to cook for another minute or so. • Meanwhile brown the butter in a skillet and add the garlic and onion. In the last possible moment add the coarsely ground red pepper and turn off the fire. Remove the eggs from the pot using a skimmer and place them in a deep plate. • Cover the eggs with plenty of yogurt and pour the hot butter over them. Serve immediately. From www.gourmet.gr

4. Pseudocode Algorithm Example Set moveCount to 1 FOR each row on the board FOR each column on the board IF gameBoard position (row, column) is occupied THEN CALL findAdjacentTiles with row, column INCREMENT moveCount END IF END FOR END FOR

5. Algorithm Example Set number counter to zero Set sum to zero While (number counter < 10) { input a number Sum = Sum + Number increment number counter by 1 } Calculate average = sum / 10

6. Labwork 1 • Write an algorithm to calculate the area of circle

7. Labwork 1 Input radius Set pi = 3.14 Calculate area = pi * radius * radius

8. Labwork 2 • Write an algorithm to calculate the sum of multiples of 3 upto 100

9. Labwork 2 Set number counter to zero Set sum to zero While (number counter < 100) { Sum = Sum + Number counter increment number counter by 3 }

10. Flowcharts • Flowcharts are schematic representations of processes • Generally the start point, end points, inputs, outputs, possible paths and the decisions that lead to these possible paths are included • Flow-charts can be created by hand or manually in most office software, but lately specialized diagram drawing software has emerged that can also be used for the purpose

11. Flowchart Symbols (Mostly Used) • Start / End symbol • Arrows • Processing steps • Input/Output • Conditional (Decision)

12. Flowchart Symbols (Others) • Document • Magnetic Tape • Display • Manual Input

13. Flowchart Example From wikipedia.org

14. Flowchart Example From smartdraw.com

15. Flowchart Example Read NAME, BALANCE, RATE Compute INTEREST as BALANCE x RATE Write (Display) NAME and INTEREST

16. Flowchart Example From wikipedia.org

17. Flowchart Example START Input N Sum =0 C = 0 Input number Sum = Sum + number C = C + 1 C = N? No Yes A = Sum / N Print A END

18. Labwork 3 • Draw a flowchart to find the sum of first 50 counting numbers

19. Labwork 3

20. Labwork 4 • Draw a flowchart to find the largest of three numbers A,B, and C.

21. Labwork 5 • Draw a flowchart to find the product of two numbers using only addition operation

22. Labwork 5

23. Labwork 6 • Draw a flowchart to find the division of two integer numbers using only subtraction operation. Find the division and remainder.

24. Labwork 6

25. Summary • Problem Solving Process • Algorithms • Components of Algorithms • Flowcharts