Using an Unordered Container
Aside from operations that manage the hashing, the unordered containers provide the same operations (find, insert
, and so on) as the ordered containers. That means that the operations we’ve used on map
and set
apply to unordered_map
and unordered_set
as well. Similarly for the unordered versions of the containers that allow multiple keys.
As a result, we can usually use an unordered container in place of the corresponding ordered container, and vice versa. However, because the elements are not stored in order, the output of a program that uses an unordered container will (ordinarily) differ from the same program using an ordered container.
For example, we can rewrite our original word-counting program from § 11.1 ...
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