1/**2* Definition for binary tree3* struct TreeNode {4* int val;5* TreeNode *left;6* TreeNode *right;7* TreeNode(int x) : val(x), left(NULL), right(NULL) {}8* };9*/10classSolution {11public:12vector<vector<int> > levelOrderBottom(TreeNode *root) {13if(!root)returnvector...
在Binary Tree Level Order Transversal的基础上难度:20,只需要对最后结果做一个倒序就好。格式是Collections.reverse(List<?> list) 1/**2* Definition for binary tree3* public class TreeNode {4* int val;5* TreeNode left;6* TreeNode right;7* TreeNode(int x) { val = x; }8* }9*/10public...
Python 代码 fromcollectionsimportdeque# 定义二叉树节点classTreeNode:def__init__(self,val=0,left=None,right=None):self.val=valself.left=leftself.right=rightdeflevelOrder(root):# 如果根节点为空,返回空列表ifnotroot:return[]# 初始化队列和结果列表queue=deque([root])result=[]whilequeue:level_siz...
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: Input: root = [3,9,20,null,null,15,7] Output: [[3],[9,20],[15,7]] Example 2: Input: root = [1] Output: [[1]] Example ...
102.binary-tree-level-order-traversal 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...
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: ...
return its bottom-up level order traversal as: [ [15,7], [9,20], [3] ] 1. 2. 3. 4. 5. # Definition for a binary tree node. # class TreeNode(object): # def __init__(self, x): # self.val = x # self.left = None ...
Binary Tree Level Order Traversal 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], 代码语言:javascript ...
分类:Tree 时间复杂度: O(n) 这种把树的节点都遍历一遍的情况时间复杂度为O(n) 空间复杂度: O(h) 树的节点的深度 107. Binary Tree Level Order Traversal II Given a binary tree, return the bottom-up level order traversal of its nodes' values. (ie, from left to right, level by level fro...
The level-by-level binary tree traversal is also abreadth-first search (BFS)approach. To achieve this traversal, we can use aqueuedata structure to ensure the order of traversal. Each element of the queue contains two values, the current tree node and the level number of the current tree ...