TreeNode root = build(); // 前序遍历:ABDEHCFG System.out.print("前序遍历:"); preOrder(root); System.out.println(); // 中序遍历:DBEHAFCG System.out.print("中序遍历:"); inOrder(root); System.out.println(); // 后序遍历:BDEHCFGA System.out.print("后序遍历:"); postOreder(roo...