How do dictionaries and sets compare in performance?

How do dictionaries and sets compare in performance?

Dictionaries and sets in Python are both implemented using hash tables, but they serve different purposes. Dictionaries store key-value pairs, while sets store unique elements. In terms of performance, both offer average time complexity of O(1) for lookups, insertions, and deletions.

Are there specific scenarios where one is better than the other?

Yes, if you need to associate values with keys, use a dictionary. If you only need to store unique items and perform membership tests, a set is more efficient.

What about memory usage between the two?

Sets generally use less memory than dictionaries because they only store keys without associated values. However, the exact difference can depend on the number of elements and the specific implementation.

Can you give an example of when to use each?

Sure! Use a dictionary when you need to store user information with unique usernames as keys. Use a set when you want to track unique visitors to a website.