Hi, Welcome back.
We're going to use the accumulator pattern a lot in this course.
Previously, you've seen how to accumulate a number,
a count, or a sum.
In this lesson, you're going to accumulate lists and strings.
With lists, you'll start with an empty list and then
you'll mutate it repeatedly by appending another item each time.
With strings, similarly, you will start with
an empty string and extend it repeatedly with
concatenation and reassignment so that you get a longer and longer string accumulated.
At the end of this lesson, you should be able to read and write code that
accumulates lists and strings. See you later!