README ¶ https://leetcode.cn/problems/binary-tree-level-order-traversal/ 102. 二叉树的层序遍历 中等 给你二叉树的根节点 root ,返回其节点值的 层序遍历 。 (即逐层地,从左到右访问所有节点)。 示例 1: 输入:root = [3,9,20,null,null,15,7] 输出:[[3],[9,20],[15,7]] 示例 2: 输入:root = [1] 输出:[[1]] 示例 3: 输入:root = [] 输出:[] 提示: 树中节点数目在范围 [0, 2000] 内 -1000 <= Node.val <= 1000 Expand ▾ Collapse ▴ Documentation ¶ Index ¶ type TreeNode Constants ¶ This section is empty. Variables ¶ This section is empty. Functions ¶ This section is empty. Types ¶ type TreeNode ¶ type TreeNode struct { Val int Left *TreeNode Right *TreeNode } Source Files ¶ View all Source files levelOrder.go Click to show internal directories. Click to hide internal directories.