René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"leetcode144：二叉树的前序遍历","articleBody":"给定一个二叉树，返回它的 **前序** 遍历。\r\n\r\n **示例:**\r\n\r\n```js\r\n输入: [1,null,2,3]  \r\n   1\r\n    \\\r\n     2\r\n    /\r\n   3 \r\n\r\n输出: [1,2,3]\r\n```\r\n\r\n**进阶:** 递归算法很简单，你可以通过迭代算法完成吗？\r\n\r\n附赠leetcode地址：[leetcode](https://leetcode-cn.com/problems/binary-tree-preorder-traversal/solution/javascriptjie-qian-xu-bian-li-er-cha-shu-by-user77/)","author":{"url":"https://github.com/sisterAn","@type":"Person","name":"sisterAn"},"datePublished":"2020-05-10T13:50:32.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/37/JavaScript-Algorithms/issues/37"}