Bimap

Bimap is a bidirectional map, which means that it can both elements are a key to each other.

The main difference with the map data structure is that all elements must be unique.

Functions

Name	Description
insert_or_assign	Inserts an element into the Bimap, according to a key. If the data already exists, its value changes.
exist	Checks if an element already exists.
erase	Erases an element from the map.
operator[]	Returns the element according to the key passed in parameters.
size	Returns the number of elements in the Bimap.