public ArrayList<Integer> findSequence(String sequence, Node node)
  {
    if (sequence.length() == 0)
    {
      return findPosition(node);
    }

    for (int i = 0; i < node.children.size(); i++)
    {
      if (sequence.startsWith(input.substring(node.children.get(i).stringStart,
          node.children.get(i).stringEnd)))
      {
        return findSequence(
            sequence.substring(node.children.get(i).stringEnd
                - node.children.get(i).stringStart), node.children.get(i));
      }
      else if (input.substring(node.children.get(i).stringStart,
          node.children.get(i).stringEnd).startsWith(sequence))
      {
        // System.out.println(input.substring(node.children.get(i).stringStart,
        // node.children.get(i).stringEnd));
        return findPosition(node.children.get(i));
      }
    }
    return null;
  }