// Constant time.
public Node AppendToFront(Node head, int data)
{
Node n = new Node(data);
n.next = head;
return n;
}
// TODO: Destructor.
public void Push(int data)
{
Node n = new Node(data);
this.head = n.AppendToFront(this.head, data);
return;
}
// Linear time since we're not tracking the tail element.
public void AppendToTail(int data)
{
Node currNode = this;
Node endNode = new Node(data);
while (currNode.next != null)
{
currNode = currNode.next;
}
currNode.next = endNode;
}
// Linear time.
public Node Find(Node head, int data)
{
while (head.next != null && head.data != data)
{
head = head.next;
}
if (head.data != data)
{
return null;
}
return head;
}
// Worst case, linear time.
public Node Delete(Node head, int data)
{
Node n = head;
if (n.data == data)
{
return head.next;
}
while (n.next != null)
{
if (n.next.data == data)
{
n.next = n.next.next;
return head;
}
n = n.next;
}
return head;
}
public Stack()
{
this.head = null;
}