++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 给定一个二叉树,返回他的层次遍历的节点的values.(提示,从左到右,一层一层的遍历) 例如: 给定一个二叉树 {1,#,2,3}, 1 \ 2 / 3 返回的层次遍历的结果是: [ [3], [9,20], [15,7] ] ++++++++++++++++++++++++++++++++++++++++++++++++++++…