What is the difference between ordered and unordered set
Set vs unordered_set
Set is an ordered sequence of unique keys whereas unordered_set is a set in which key can be stored in any order, so unordered. Set is implemented as a balanced tree structure that is why it is possible to maintain order between the elements (by specific tree traversal). The time complexity of set operations is O(log n) while for unordered_set, it is O(1).