Loops

Loops are a way of making code appear "cleaner" and more efficient when repeated code is used.

Parts of a Loop

1. Kind of loop (e.g. while, for, foreach)

2. Initialization of a control variable (e.g. int count = 1; int i = 0; etc.) A control variable is a temporary variable used to iterate (increase or decrease) to limit the number of times a loop code runs.

3. Test conditions (What needs to be true?)

4. Update the control variable (e.g. i++; i -= 5; etc.)

5. Action to take (What is in the code block)

Types of Loops

While loops

For loops

Foreach loops

Nested Loops

A loop INSIDE a loop? ? Heck, yeah!

The loops work the same inside other loops, BUT a different control variable will need to be used.

Generally, since i is often used, nested loops continue the alphabet: j, then k, then l...

Example:

String[] names = { "Fluffy", "Nugget", "Pumpkin" };

for (int i = 0; i < names.length; i++) {
	for (int j = 0; j < 3; j++) {
		println(names[i]);
	}
}

Prints:

Fluffy Fluffy Fluffy Nugget Nugget Nugget Pumpkin Pumpkin Pumpkin