Node(TreeNode* newtNode,intnewlevel): tNode(newtNode), level(newlevel) {} };classSolution {public: vector<vector<int> > levelOrderBottom(TreeNode *root) { vector<vector<int> >ret;if(!root)returnret;//push rootNode* rootNode =newNode(root,0); queue<Node*>Nqueue; Nqueue.push(root...
代码 publicArrayList<ArrayList<Integer>>levelOrder(TreeNode root) {//Note: The Solution object is instantiated only once and is reused by each test case.ArrayList<ArrayList<Integer>> ans=newArrayList<ArrayList<Integer>>();if(root==null)returnans; Queue<TreeNode> list=newLinkedList<TreeNode>();...
[Leetcode][python]Binary Tree Zigzag Level Order Traversal,题目大意按之字形遍历二叉树(一正一反)解题思路来自:链接解题思路:这道题和上一题层序遍历那道题差不多,区别只是在于奇数层的节点要翻转过来存入数组。代码:代码BFSclassSolution(object):defzigzagLeve
leetcode 107. Binary Tree Level Order Traversal II Given a binary tree, return thebottom-up level ordertraversal of its nodes' values. (ie, from left to right, level by level from leaf to root). For example: Given binary tree[3,9,20,null,null,15,7], 3 / \ 9 20 / \ 15 7 1...
/ 15 7 return its level order traversal as: [ [3], [9,20], [15,7] ] 【Idea】 这个题也不难, 因为O(n)还蛮能打的, 所以po一下 BFS要更好写一些。 这里每层遍历node时直接用了for,没有用queue,不然还要另起个变量标记 【Solution】 ...
这道题和LeetCode笔记:107. Binary Tree Level Order Traversal II是姊妹题,解题思路都是一样的,只是结果要求的顺序是反的,同样有两种方法,也就是经常说到的DFS深度优先遍历和BFS广度优先遍历。 BFS: 广度优先遍历就是一层层地攻略过去,把每一层的所有节点都记录下来再走向下一层。因为每层会有多个节点,不是简...
Leetcode 102. Binary Tree Level Order Traversal 题目描述 题目链接:https://leetcode-cn.com/problems/binary-tree-level-order-traversal/ 给定一个二叉树,返回其按层次遍历的节点值。 (即逐层地,从左到右访问所有节点)。 例如: 给定二叉树: [3,9,20,null,null,15,7], 返回其层次遍历结果: 解题方案...
Can you solve this real interview question? Binary Tree Level Order Traversal - Given the root of a binary tree, return the level order traversal of its nodes' values. (i.e., from left to right, level by level). Example 1: [https://assets.leetcode.c
DFS代码参考地址:LeetCode Binary Tree Level Order Traversal 其他题目: Binary Tree Level Order Traversal II 层次遍历从低往root结点输出,如Given binary tree{3,9,20,#,#,15,7}, 3 / \ 9 20 / \ 15 7 return its level order traversal as: ...
Leetcode Binary Tree Zigzag Level Order Traversal Binary Tree Zigzag Level Order Traversal Given a binary tree, return thezigzag level ordertraversal of its nodes' values. (ie, from left to right, then right to left for the next level and alternate between)....