List unordered list implementation
List implementation: unordered list UnorderedLIst
Next, consider how to add items to the unordered list, the add method to achieve.
Since the order is not limited and unordered list items between
new data item can be added to any position of the original table
in accordance with performance considerations implemented, it should be added to a position most easily added.
To access the list structure to the whole chain of all data items must start back from the table one by one to find the head head along the next link
So add a new data item most efficient location is the header, the first position of the entire list of
