static public Node ListAddtoEnd(Node head, int val)
{
//Special case of empty list.
if (head == null)
return new Node(val);
//Otherwise, need reference to last node
Node tail = head;
while (tail.next != null)
tail = tail.next;
tail.next = new Node(val);
return head;
}
static public Node ListAddInOrder(Node head, int val)
{
//This is your ICA for next Monday. Have fun!!!!
//***Two special cases! (1) Empty list, (2) Insert at head
//If I want to know the value of the node after my reference
//Current.Next.Value is the value of the node after Current.
//Current.Next.Next.Value is the value of the node after that. BEWARE OF NULLS!
//If (Current.Next != Null) will be needed.
//THIS IS THE SOLUTION
//Case 1 - Empty list
if (head == null)
{
//Pretty easy
Node newNode = new Node(val); //Pretty new node
//Aaand that's my whole list, so just return it.
return newNode; //This is the new reference to the head of the list.
}
//Case 2 -- Add in front of head of the list (another case where
// we need a new head)
if(head.value > val)
{
Node newHead = new Node(val);
newHead.next = head; //Connect to old head.
return newHead;
}
//Case 3 -- Belongs somewhere else in the list
//If I made it here, then that's the case. No need for an if.
//Find my insertion point
Node current = head; //Pointer to head
while (current.next != null && current.next.value < val) //While my current is not pointing to insert point
current = current.next;
//Current must now point to my insertion point, so insert
Node reallynewNode = new Node(val);
reallynewNode.next = current.next;
current.next = reallynewNode;
return head;
}
public Node next; //Actually a reference to a node, not a node inside this one
public Node(int val)
{
value = val;
next = null; //Null means not connected
}
static public void PrintList(Node head)
{
if (head != null)
{
Console.Write(head + " ");
PrintList(head.next);
}
}
static public void PrintListInReverse(Node head)
{
if (head != null)
{
PrintListInReverse(head.next);
Console.Write(head + " ");
}
}
