package tree;

class Tree<T> {

    private Node<T> root = null;
    
    public Tree(T data) {
        root = new Node(data);
    }
    
    public Node getRoot() {
        return root;
    }
}
	

package tree;

import java.util.ArrayList;
import java.util.List;

public class Node<T> {

    private T data = null;
    private List<Node> children = new ArrayList<>();
    private Node parent = null;

    public Node(T data) {
        this.data = data;
    }

    public void addChild(T data) {
        Node<T> node = new Node<>(data);        
        node.parent = this;
        children.add(node);
    }

    public List<Node> getChildren() {
        return children;
    }

    public Node getParent() {
        return parent;
    }

    
    public T getData() {
        return data;
    }

    public void setData(T data) {
        this.data = data;
    }

}