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public class Item<E extends Comparable<E>> {
	private E value;
	private Item<E> previous;
	private Item<E> next;

	public Item(E value) {
		this.value = value;
		previous = null;
		next = null;
	}

	public void addBefore(Item<E> newItem) {
		newItem.next = this;
		newItem.previous = this.previous;
		if (this.previous != null)
			this.previous.next = newItem;
		this.previous = newItem;
	}

	// append at tail
	public void addAfter(Item<E> newItem) {
		newItem.previous = this;
		this.next = newItem;
	}

	public E getValue() {
		return value;
	}

	public Item<E> getNext() {
		return next;
	}
}

public class MyList<E extends Comparable<E>> {
	private Item<E> head;

	public void add(E value) {
		if (head == null)
			head = new Item<E>(value);
		else {
			Item<E> temp = head;
			Item<E> newItem = new Item<E>(value);
			do {
				if (value.compareTo(temp.getValue()) < 0) {
					temp.addBefore(newItem);
					if (head == temp)
						head = newItem;
					return;
				}
				if (temp.getNext() == null)
					break;
				temp = temp.getNext();
			} while (true);
			temp.addAfter(newItem);
		}
	}

	public void print() {
		Item<E> temp = head;
		while (temp != null) {
			System.out.println(temp.getValue());
			temp = temp.getNext();
		}
	}
}

public class Main {
	public static void main(String[] args) {
		MyList<Integer> list = new MyList<Integer>();
		list.add(5);
		list.add(3);
		list.add(7);
		list.add(4);
		list.print();
	}
}