// Add item after targeted number
public void AddAfter(int n, int target)
{
if (Head == null)
{
return;
}
DLLNode newNode = new DLLNode {
Val = n
};
DLLNode current = Head;
while (current != null)
{
if (current.Val == target)
{
if (current.Next != null)
{
current.Next.Prev = newNode;
}
newNode.Next = current.Next;
current.Next = newNode;
newNode.Prev = current;
return;
}
current = current.Next;
}
}
// Remove item from Doubly Linked List
public void Remove(int n)
{
if (Head == null)
{
return;
}
if (Head.Val == n)
{
Head = Head.Next;
return;
}
DLLNode curr = Head;
while (curr.Next != null)
{
curr = curr.Next;
if (curr.Val != n)
{
continue;
}
if (curr.Next != null)
{
curr.Next.Prev = curr.Prev;
}
if (curr.Prev != null)
{
curr.Prev.Next = curr.Next;
}
return;
}
Console.WriteLine("Not Found");
}
static void PrintLinked(DLLNode node)
{
while (node != null)
{
Console.WriteLine(node.Val);
node = node.Next;
}
}
// Add item to the beginning of the LinkedList
public void AddFirst(int n)
{
DLLNode newNode = new DLLNode {
Val = n
};
if (Head == null)
{
Head = newNode;
return;
}
newNode.Next = Head;
Head.Prev = newNode;
Head = newNode;
}
// Add last item to the linkedlist
public void AddLast(int n)
{
DLLNode newNode = new DLLNode {
Val = n
};
if (Head == null)
{
Head = newNode;
return;
}
DLLNode current = Head;
while (current.Next != null)
{
current = current.Next;
}
current.Next = newNode;
newNode.Prev = current;
}