Section Recap

You now use maps and sets for efficient lookups.

$1.$ map stores key-value pairs with $O(\log n)$ lookup

$2.$ set stores unique values in sorted order

$3.$ unordered versions offer $O(1)$ average lookup

$4.$ Use maps for counting frequencies and associations

Good job. You can now do fast lookups. Next, you will learn pairs and tuples for grouping values.