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# Average of Levels in Binary Tree

Updated: Mar 24, 2021

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:

1. The range of node's value is in the range of 32-bit signed integer.

Solution:

```/**
* Definition for a binary tree node.
* public class TreeNode {
*     int val;
*     TreeNode left;
*     TreeNode right;
*     TreeNode() {}
*     TreeNode(int val) { this.val = val; }
*     TreeNode(int val, TreeNode left, TreeNode right) {
*         this.val = val;
*         this.left = left;
*         this.right = right;
*     }
* }
*/
class Solution {

public List<Double> averageOfLevels(TreeNode root) {
List<Double> result = new ArrayList<>();
List<Integer> list = new ArrayList<>();
while(!queue.isEmpty())
{
int size=queue.size();
for(int i=0;i<size;i++)
{
TreeNode current=queue.poll();
}
double sum=0.0,avg=0.0;
for(int i:list)
{
sum+=i;
}
avg=sum/list.size();
list.clear();
}
return result;
}
}```