Leetcode 637 Average of Levels in Binary Tree

Given the root of a binary tree, return the average value of the nodes on each level in the form of an array. Answers within 10-5 of the actual answer will be accepted.

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Input: root = [3,9,20,null,15,7]
Output: [3.00000,14.50000,11.00000]
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].
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Input: root = [3,9,20,15,7]
Output: [3.00000,14.50000,11.00000]
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  • Breadth first search (BFS) ile her seviyedeki değerleri alırız ve daha sonrasında değerlerin ortalamasını alırız.
 def averageOfLevels(self, root: TreeNode) -> List[float]:
        results = []        
        queue = [root]
        
        while queue:
            size = len(queue)
            level = []
            
            for i in range(size):
                node = queue.pop(0)
                
                level.append(node.val)
                
                if node.left:
                    queue.append(node.left)
                if node.right:
                    queue.append(node.right)
                    
                
            results.append(sum(level) / len(level))