This method returns the amount of elements currently present in the tree.
This is a draft version, as it uses the slice operator of the class. So getting this number has a complexity
proportional to n. As this functionaly is not seen as crucial, it is enough for the first time.
This method returns the amount of elements currently present in the tree. This is a draft version, as it uses the slice operator of the class. So getting this number has a complexity proportional to n. As this functionaly is not seen as crucial, it is enough for the first time.