// Source code example for "A Practical Introduction
// to Data Structures and Algorithm Analysis"
// by Clifford A. Shaffer, Prentice Hall, 1998.
// Copyright 1998 by Clifford A. Shaffer

interface GenTree {         // General tree ADT
  public void clear();      // Clear the tree
  public GTNode root();     // Return the root
  // Make the tree have a new root with children first and sib
  public void newroot(Object value, GTNode first, GTNode sib);
  public void newleftchild(Object value); // Add left child
} // interface GenTree