static void Main(string[] args)
{
//Create the first node
MyDoublyLinkedList node = new MyDoublyLinkedList("Ardhendu");
//Assign head
MyDoublyLinkedList head = node;
// array variable to hold each person's name to be inserted into the list
string[] names = { "Tom", "Jones", "David", "Andrew", "Peter", "Mark", "Collette", "Dave", "Dan" };
//Add 9 more consecutive nodes (Tom, Jones, David, Andrew, Peter, Mark, Collette, Dave, Dan)
for (int i = 2; i <= 10; i++)
{
node.InsertNextNode(node, names[(i - 2)]);
node = node.next;
}
//Traverse the linked list from head to tail
node.TraverseForward(head);
//Delete Peter node and then traverse forward
head.next.next.next.next.DeleteNode();
node.TraverseForward(head);
//Insert Peter after Mark and then traverse backward
node.InsertNextNode(head.next.next.next.next.next, "Peter");
node.TraverseBackward(head.next.next.next.next.next.next.next.next.next);
}
//Traverse Backward
public void TraverseBackward(MyDoublyLinkedList node)
{
//Print the values stored in each node from current to head
Console.WriteLine("Traversing in backward direction...");
while (node != null) //Traverse from the current node
{
Console.WriteLine(node.name); // print out that node's associated name
node = node.prev; // update node location - go one previous
}
}
//Traverse forward
public void TraverseForward(MyDoublyLinkedList node)
{
//Print the values stored in each node from current to tail
Console.WriteLine("Traversing in forward direction...");
while (node != null) //Traverse from the current node
{
Console.WriteLine(node.name); // Print out the current node's name that is associated with that node
node = node.next;
}
}
//Insert a new node with a value BEFORE the current node
public void InsertPrevtNode(MyDoublyLinkedList current, string value)
{
MyDoublyLinkedList node = new MyDoublyLinkedList(value);
if (current.prev == null)
{
//Insert in the beginning
node.next = current; // inserts before the beginning, making the new node at the beginnin
}
else
{
//Insert in the middle
current.prev = node;
node.next = current;
prev.next = node;
node.prev = prev;
}
}
//Insert a new node with a value AFTER the current node
public void InsertNextNode(MyDoublyLinkedList current, string value)
{
MyDoublyLinkedList node = new MyDoublyLinkedList(value);
if (current.next == null)
{
//Insert at the end and easy to handle
current.next = node;
node.prev = current;
}
else
{
//Insert in the middle
node.next = current.next; // update the new node's next pointer to now be current -> next
node.prev = current; // update the new node's prev to point to current
current.next.prev = node; // update the next node's prev to point to the new node as it has been sloted in before it
current.next = node; // current node now points to the new node
}
}
public void DeleteNode()
{
//Check for ERROR if you are deleting a node which is referred by many pointers.
//Update all these pointers before deleting (releasing) memory!
if (next == null)//last node
{
//Delete the last node
prev = null;
}
else if (prev == null)
{
//Delete head node
next = null;
}
else
{
//Update the next node pointer and reset the deleted node to null
next = next.next; // reassign pointer to the node that comes after the next
next.next.prev = null; // delete the node that is previous of the newly pointed to node
}
}
//Constructor with parameter
public MyDoublyLinkedList(string value)
{
name = value;
next = null;
prev = null;
}
//Default Constructor
public MyDoublyLinkedList()
{
name = "";
next = null;
prev = null;
}