1 public BiTNode createBiTree() 2 { 3     Scanner input = new Scanner(System.in); 4     int k = input.nextInt(); 5     if(k == -1) 6         return null; 7          8     BiTNode node = new BiTNode(k); 9     node.lchild = createBiTree();10     node.rchild = createBiTree();11     return node;12 }13 14 public static void main(String[] args)15 {16     BiTree t = new BiTree();17     t.root = t.createBiTree();  //Java的方法均为按值传递 故应该有返回值(区别于C++) 18 }