C++ Language/Std/Stl/CollectionClasses/SortedCollections

Some STL collection classes are "sorted", in the sense that the class' items are internally stored using a tree data structure. Each item contains a "key", and the tree data structure maintains a property whereby the items are sorted by that key. As a result, client code can still iterate over the data structure from a "beginning" (item having the smallest key) to an "ending" (item having the largest key), even though that data isn't being linearly-stored. To define the sorting of keys, a sorted collection object is associated with a "sort-class" object. A Pair as one Item Tuple Map Multimap Set Multiset Hash-Table