import java.util.*;

class Node implements Cloneable {
  public Object type = null;
  public Node[] children = new Node[10];
  public int numchildren = 0;

  Node() {
  }

  Node(Object t) {
    type = t;
  }

  public void addChild(Node n) {
    numchildren++;
    if (numchildren > children.length) {
      Node[] temp = new Node[children.length+10];
      for (int i = 0; i < children.length; i++)
        temp[i] = children[i];
      children=temp;
    }
    children[numchildren-1] = n;
  }

  public Node newChild() {
    Node temp = new Node();
    addChild(temp);
    return temp;
  }

  public Object clone() {
    Node n = new Node(this.type);
    for (int i=0; i<numchildren; i++) n.addChild((Node) this.children[i].clone());
    return n;
  }
}