Sum of all nodes in Binary Tree

Easy

Given a binary tree that contains nodes with numbers, calculate the sum of all the nodes in the tree.

For example, let's say you're given the following binary tree:

Your fuction should return 27, the sum of all nodes.

Try it

class BinaryTreeNode:
    def __init__(self, data):
        self.data = data
        self.left = None
        self.right = None

def tree_sum(tree: BinaryTreeNode) -> int:
    # implement tree_sum
    return 0

1class BinaryTreeNode:
2    def __init__(self, data):
3        self.data = data
4        self.left = None
5        self.right = None
6
7def tree_sum(tree: BinaryTreeNode) -> int:
8    # implement tree_sum
9    return 0
10

Solution

9 Essential Trees & Graphs Coding Interview Problems

Master Trees & Graphs by trying the coding challenges below.

1.Inorder TraversalEasy
2.Tree SumEasy
3.Tree HeightEasy
4.LCAMedium
5.Max Path SumHard
6.Search mazeMedium
7.Number of islandsMedium
8.Kth SmallestMedium
9.Sort K ArraysHard

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