Computer Science 100

Computational Expression

Gregory M. Kapfhammer


flickr photo by wocintechchat.com shared under a CC (BY) license

Color Scheme

Key Concept

Corresponding Diagram

In-Class Discussion

In-Class Activity

Details in the Textbook

Switch Statements

An alternative to using if statements

Cannot encode complex boolean expressions

Sometimes simpler for a programmer to understand

Which approach do you prefer? Why did you pick it?

See Section 6.1 for more details!

Do statements

Please see page 274 for an example!

Work with a partner to compare while and do-while loops

What is the key difference?

How do pick between these options?

Can you draw a picture to visualize their execution?

Visualize these loops with a diagram

For Statements

When is it best to use a while loop?

What if we know the number of iterations?

We should try to use the for loop!

What is the structure of a for loop?

Visualize the for loop with a diagram

Computing Multiples

Run the git pull command!

Build the ComputeMultiples.java program

Run this program like it was on page 282

Try five different inputs for this program

Record one output of this program

How does this program use for loops?

Document each part of the code

Master the use of a complex for loop

Any questions about for loops?

Printing Stars

This program uses iteration constructs

We will investigate this program during a practical

Do you understand how to this program works?

Could you extend this program with new loops?

Iteration Constructs

Three basic loop statements are functionally equivalent

What if we want to run the loop body at least one time?

What if we know the number of times iteration will occur?

What if we want to use an Iterator?

Make sure that you understand the trade-offs!

Extra Fun

Create a program called PrintStatusBar.java

The program should accept two command-line arguments

The first input should be the number of printed symbols

The second input should be the printed symbols

Print the specified number of symbols in the terminal

Can you create, compile, and run this program?

What output does it produce?

Any questions about iteration constructs?