Programming Fundamentals/Conditions/Compound Conditions

Compound conditions perform different computations or actions depending on whether multiple combined programmer-specified Boolean conditions evaluate to true or false. This activity introduces compound conditions. This activity will help you understand how to use compound conditions in a program.

Objectives

• Understand compound condition concepts.
• Understand how compound conditions are specified in a program.
• Create truth tables for "and" and "or" logical operators.
• Single-step through a program to observe nested condition execution.

Prerequisites

Learners should already be familiar with nested conditions.

Introduction

Flowgorithm nested conditions

Review the flowchart example on the right.

Questions

• What flowcharting symbol is used to indicate a condition?
• How are compound conditions structured?
• What is the difference between "and" and "or"?
• What are truth tables?
• What do "and" and "or" truth tables include?

Activity

With a partner, perform the following:

1. Using a visual programming language, create a program matching the flowchart on the right.
2. Save the program.
3. Test the program to verify that it works correctly.
4. Trade places, so that both partners have an opportunity to "drive" the visual programming environment.
5. Change the environment to use a slow run speed and/or step through the program one shape at a time.
6. Working together, identify the compound conditions that would be used to either convert Fahrenheit temperature to Celsius or convert Celsius temperature to Fahrenheit, depending on user choice.

Applications

• Identify specific steps which must be followed when creating a program using compound conditions.
• Discuss your activity experience with your classmates. What surprised you? What have you learned that you can apply to your own school or work environment?