human
Doubly Linked List | Set 1 ( Introduction and Insertion ) | Add a node at the end of the DLL.
1. allocate node 2. put in the data.
3. This new node is going to be the last node , so make next of it as NULL.
4. If the Linked List is empty , then make the new node as head.
5. Else traverse till the last node.
6. Change the next of last node.
7. Make last node as previous of new node"
Solution in Python:
assistant
#Here is code to doubly Linked List and the other steps required.
 def append ( self , new_data ) :
	new_node = Node ( data = new_data )
	last = self . head
	new_node . next = None
	if self . head is None :
		new_node . prev = None
		self . head = new_node
		return
	while ( last . next is not None ) :
		last = last . next
	last . next = new_node
	new_node . prev = last