题目 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], 3 / \ 9 20 / \ 15 7 返回其层次遍历结果: [ [3], [9,20], [15,7] ] 考点 思路 代码 newcoder /* struct TreeNode { int val; struct TreeNode *left; struct TreeNode *right; TreeNode(int x) : va…

要求 对二叉树进行层序遍历 实现 返回结果为双重向量,对应树的每层元素 队列的每个元素是一个pair对,存树节点和其所在的层信息 1 Definition for a binary tree node. 2 struct TreeNode { 3 int val; 4 TreeNode *left; 5 TreeNode *right; 6 TreeNode(int x) : val(x), left(NULL), right(NULL) {} 7 }; 8 9 class Solution {…

从上往下打印二叉树这个是不分行的,用一个队列就可以实现 class Solution { public: vector<int> PrintFromTopToBottom(TreeNode* root) { vector<int> result; queue<TreeNode* > container; if(root == NULL) return result; container.push(root); ){ TreeNode* rot = container.f…

题目: Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example: Given binary tree {3,9,20,#,#,15,7}, 3 / \ 9 20 / \ 15 7 return its level order traversal as: [ [3], [9,20], [15,7]…

Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binary tree [3,9,20,null,null,15,7], 3 / \ 9 20 / \ 15 7 return its level order traversal as: [ [3], [9,20], [15,7…

""" Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example: Given binary tree [3,9,20,null,null,15,7], 3 / \ 9 20 / \ 15 7 return its level order traversal as: [ [3]…

问题描述: Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binary tree [3,9,20,null,null,15,7], 3 / \ 9 20 / \ 15 7 return its level order traversal as: [ [3], [9,20],…

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], 3 / \ 9 20 / \ 15 7 返回其层次遍历结果: [ [3], [9,20], [15,7] ] class Solution { public: vector<vector<int> > levelOrder(TreeNode* root) { vector<vector<int> > res…

Given a binary tree, return the bottom-up level order traversal 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 return its bottom-up level or…

Given a binary tree, return the bottom-up level order traversal of its nodes' values. (ie, from left to right, level by level from leaf to root). For example:Given binary tree{3,9,20,#,#,15,7}, 3 / \ 9 20 / \ 15 7 return its bottom-up level order tra…