While Loop

A while loop keeps going as long as a test is true.

You check first. Then you run. Then you check again.

Think of eating cookies while the jar still has cookies.

Basic while

Write while (condition) { ... }.

Something must change

Inside the loop, update the value that the test uses.

If nothing changes, the loop may never stop.

Unknown counts

while is nice when you do not know the exact count at the start.

You just know the stop rule.

do while

do while runs the block at least once.

Then it checks the condition.

while vs for

for is great when start, stop, and step are clear.

while is great when the stop rule is a state that changes over time.

Tip: Before you run a while loop, point to the line that moves you closer to stopping.