Memento Capable LinkedList: Using the "memento" pattern create a LinkedList class that supports state recovery.
You can extend java. util. LinkedList or create your own but you must support the following methods:
add(E e)
addFirst(E e)
addLast(E e)
clear()
contains(Object o)
get(int index)
getFirst()
getLast()
remove(int index)
removeFirst()
removeLast()
remove()
size()
Memento createMemento()
void restoreMemento(Memento state)