C++ Set vs Unordered Set

What are the main differences between C++ set and unordered_set?

C++ set is ordered and uses a binary search tree, while unordered_set is unordered and uses a hash table.

Which one is more efficient for searching?

Unordered_set generally offers average O(1) time complexity for search operations, while set has O(log n).

Are there any scenarios where I should prefer set over unordered_set?

Yes, if you need to maintain order or perform range queries, set is the better choice.

Can you give an example of when to use unordered_set?

Use unordered_set when you need fast lookups and don't care about the order of elements, like in a membership test.