It’s been a “while”

Great! You figured the for loop out. It’s convenient to use when the number of repetitions is known in advance, even before the start of the loop. For example, when you know the number of pages in the document or the number of days.

But there are situations where the number of repetitions is not known beforehand. For example, biathlon: shoot at targets until you hit every target.

In these cases, a while loop is useful: it repeats the actions while its condition is true.

while (condition) {
  actions
}

The actions specified in the loop will be executed again and again until the condition returns false.

Let’s practice using a while loop before the boss gives us yet another job to work on.

When on break from work, the boss likes to play darts. He is trying to set a record: to score the maximum number of points in a series of throws without a miss. As soon as he misses, the series ends (and judging by the holes in the wall, he misses quite often).

We need a simple program to track these attempts. The muffin.getScore() command gives us the score for the next throw: a number from 1 to 20 for a hit, or -1 for a miss.