public int Pop()
{
if (head == null)
{
throw new Exception("Stack is empty");
}
var node = head;
head = head.next;
return(node.data);
}
public void Push(int val)
{
Linkedlist <int> node = null;
if (head == null)
{
head = new Linkedlist <int>();
node = head;
head.data = val;
}
else
{
node = new Linkedlist <int>();
node.data = val;
node.next = head;
head = node;
}
}