标签：pen out float return class binary normal each type
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. Hence return [3, 14.5, 11].
Note:
# Definition for a binary tree node.# class TreeNode(object):# def __init__(self, x):# self.val = x# self.left = None# self.right = Noneclass Solution(object):def averageOfLevels(self, root):""":type root: TreeNode:rtype: List[float]"""if(not root):return 0result = []queue = [root]while(queue):count = len(queue)sum = 0for i in range(0, count):node = queue.pop(0)sum += node.valif(node.left):queue.append(node.left)if(node.right):queue.append(node.right)result.append(sum * 1.0 / count)return result
637. Average of Levels in Binary Tree 二叉树每一层的平均值
标签：pen out float return class binary normal each type
原文地址：http://www.cnblogs.com/xiejunzhao/p/7142333.html
