2-RBTree.java

      //the second line for search
      inStr = in.nextLine().trim().split(" ");
      for (String str : inStr) {
        if (!str.isEmpty()) {
          RBTree.Node node = tree.find(Integer.parseInt(str));
          node = node == null ? null : node.right;
          out.print((node == null ? "null" : node.value) + " ");
          System.out.print((node == null ? "null" : node.value) + " ");
        }
      }