public class Queue implements Iterable{
private java.util.LinkedList list = new java.util.LinkedList();
public Queue(){}
public Queue(T data){
enqueue(data);
}
public int size(){
return list.size();
}
public boolean isEmpty(){
return size() == 0;
}
public T peek(){
if(isEmpty()) throw new RuntimeException('The queue is empty');
return list.peekFirst();
}
public T dequeue(){
if(isEmpty()) throw new RuntimeException('The queue is empty');
return list.removeFirst();
}
public void enqueue(T data){
list.addLast(data);
}
@Override public java.util.Iterator iterator(){
return list.iterator();
}
}