// BinaryNode class; stores a node in a tree.
// Original source: http://www.cs.fiu.edu/~weiss/dsj2/code/BinaryNode.java
// Modifications to Weiss's code and comments by DIS
// *******************PUBLIC OPERATIONS**********************
// void printPostOrder( ) --> Print a postorder tree traversal
// void printInOrder( )   --> Print an inorder tree traversal
// void printPreOrder( )  --> Print a preorder tree traversal

public class BinaryNode {
    
    private Object     element;
    private BinaryNode left;
    private BinaryNode right;
    
    public BinaryNode( ) {
        this( null, null, null );
    }

    public BinaryNode(Object theElement) {
        this( theElement, null, null );
    }
    
    public BinaryNode( Object theElement, BinaryNode lt, BinaryNode rt ) {
        element = theElement;
        left    = lt;
        right   = rt;
    }

    // Print tree rooted at current node using preorder traversal.
    public void printPreOrder( ) {
        System.out.println( element );       // Node
        if( left != null )
            left.printPreOrder( );           // Left
        if( right != null )
            right.printPreOrder( );          // Right
    }
    
    // Print tree rooted at current node using postorder traversal.
    public void printPostOrder( ) {
        if( left != null )
            left.printPostOrder( );          // Left
        if( right != null )
            right.printPostOrder( );         // Right
        System.out.println( element );       // Node
    }
    
    // Print tree rooted at current node using inorder traversal.
    public void printInOrder( ) {
        if( left != null )
            left.printInOrder( );            // Left
        System.out.println( element );       // Node
        if( right != null )
            right.printInOrder( );           // Right
    }

    public Object getElement( ) { return element; }
    public BinaryNode getLeft( ) { return left; }
    public BinaryNode getRight( ) { return right; }
    public void setElement( Object x ) { element = x; }
    public void setLeft( BinaryNode t ) { left = t; }
    public void setRight( BinaryNode t ) { right = t; }

} // Class BinaryNode