Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array. 这个是一个二叉树层序遍历题,不同的是需要对每层取平均值。 Example 1: Input: 3 / \ 9 20 / \ 15 7 Output: [3, 14.5, 11] Explanation: The average value of nodes on level...
637. Average of Levels in Binary Tree # 题目# Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array. Example 1: Input: 3 / \ 9 20 / \ 15 7 Output: [3, 14.5, 11] Explanation: The average value of nodes on level 0 is ...
1#Definition for a binary tree node.2#class TreeNode(object):3#def __init__(self, x):4#self.val = x5#self.left = None6#self.right = None78classSolution(object):9defaverageOfLevels(self, root):10"""11:type root: TreeNode12:rtype: List[float]13"""14levels = [[root]]#将要...
Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array. Example 1: Input: 3 / \ 9 20 / \ 15 7 Output: [3, 14.5, 11] Explanation: The average value of nodes on level 0 is 3, on level 1 is 14.5, and on level 2 is 11...
Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array. Example 1: Input: 3 / \ 9 20 / \ 15 7 Output: [3, 14.5, 11] Explanation: The average value of nodes on level 0 is 3, on level 1 is 14.5, and on level 2 is 11...
* Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */classSolution{public:vector<double>averageOfLevels(TreeNode*root){vector<int>count;vector<double>res;average...
(来源:https://leetcode.com/problems/average-of-levels-in-binary-tree/) 本质上就是个遍历啊 非递归方法里,null永远不要存进stackorqueue 递归 classNodeSum{doublesum;intnum;}classSolution{publicList<Double>averageOfLevels(TreeNoderoot){List<Double>avgList=newArrayList<>();if(root==null){returnavg...
leetcode Add to List 637. Average of Levels in Binary Tree,就是对二叉树每一层求平均值。开始想法用层次遍历,然而又不知道该点是在哪一层。所以要求没一点的深度,而通过先序遍历递归求没一点的深度的过程中。好像并不需要再去层次遍历,结果就已经很明显了。要注意l
637. Average of Levels in Binary Tree Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array. Example 1: Input: 3 / 9 20 / 15 7 Output: [3, 14.5, 11] Explanation: The average value of nodes on level 0 is 3, on level 1...
Let Vk (n) be the minimum average number of pairwise comparisons needed to find the k-th largest of n numbers (k≥2), assuming that all n! orderings are equally likely. D. W. Matula proved that, for some absolute constant c, Vk(n)- n ≤ ck log log n as n →∞. In the pr...