The Standard Template Library (STL) is a set of C++ template classes to provide common programming data structures and functions such as lists, stacks, arrays, etc. It is a library of container classes, algorithms, and iterators. It is a generalized library and so, its components are parameterized. Working knowledge of template classes is a prerequisite for working with STL.
- Algorithms
- Containers
- Functions
- Iterators
A multiset is an STL container that can contain multiple objects which have the same value which is stored in a well-defined manner. The multisets are almost similar to sets, except in sets only unique elements are allowed but in multisets, multiple elements with the same values are also allowed.
- The STL multisets can be used in the program by adding two header files.
- The first is a set and the other is an iterator.
Unordered maps are the containers that contain key-value pairs in a randomised manner.Every key present in the unordered map is distinct though their key values can be the same. The unordered map is implemented internally using hashing.
- The STL unordered map can be used in the program by adding two header files.
- The first is unordered_map and the other is an iterator.