public class Stack <E> 
{
    private LinkedList <E> list;
    public Stack() {list = new LinkedList();}
    
    public void push(E data) {
        list.addLast(data);
    }
    
    public E pop() {
        return list.removeLast();
    }
    
    public E peek() {
        return list.getLast();       
        
    }
    
    public boolean isEmpty()
    {
        return list.isEmpty();
    }

}