1. ME 142 Engineering Computation I
Fundamentals of Procedural Computer Programming

2. Key Concepts
Algorithm Development Flowcharting

3. Algorithm A set of instructions for solving a problem
A step-by-step procedure for obtaining a solution to a given class of problems
Example:
recipe

4. Algorithm Most programs consist of the following simplified algorithm:
Input
Process
Output

5. Algorithm Example
Develop the algorithm to find the area of a rectangle:
Input:
Enter length, width
Process:
Multiply length times width to obtain area
Area = length * width
Output:
Display area

6. Flowcharts A flowchart is a pictorial representation of an algorithm.
Steps of the algorithm are enclosed in boxes of various shapes.
The flow of control is indicated by lines connecting the boxes.
An arrow is placed on each line to indicate direction of flow.

7. Standard Flowcharting Symbols
Terminator box. Used to show both the start and stop of an algorithm.
Operation box. Used for computations, assignment statements, definitions, etc.
Input/Output box. Used to indicate items to be read or written by the algorithm.

8. Standard Flowcharting Symbols
Decision box. Used to pose questions in determining which branch to follow for the next instruction.
Connector circle. Used to connect parts of the flowchart from page to page, etc.

9. Flowcharting Example Area of a Rectangle
Start
Enter
length, width
area =
length * width
Display
area
Stop

10. Flowcharting Guidelines
Flowcharts are written to be a guide for writing actual code. The flowchart should have just enough detail for you to code from.
Think in terms of small, sequential operations
What needs to be done
What order, i.e., what must come first, etc