avg-levels-bin-tree.py

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
    def averageOfLevels(self, root: TreeNode) -> List[float]:
        
        def bfs(root):
            from collections import deque
            queue = deque()
            queue.append(root)
            levels = [[root.val]]
            while queue:
                thatlevel=[]
                node = queue.popleft()
                # print(node.val)
                
                if node.left:
                    queue.append(node.left)
                    thatlevel.append(node.left.val)
                if node.right:
                    queue.append(node.right)
                    thatlevel.append(node.right.val)
                levels.append(thatlevel)
            
            return levels
        
        if root is None:
            return []
        
        levels = bfs(root)
        print(levels)
        avgs = []
        for level in levels:
            if level:
                avgs.append(sum(level)/len(level))
        
        return avgs