aloalgoBinary Tree Sum
Easy
You are given the root of a binary tree.
Your task is to calculate the sum of all node values in the tree.
Return the total sum of all node values.
Example 1
Input
Output
10
Explanation:
The sum of all node values (1 + 2 + 3 + 4) is 10.
Example 2
Input
None
Output
0
Explanation:
An empty tree has a sum of 0.
Example 3
Input
Output
1
Explanation:
A single node tree has a sum equal to its value.
Input
Output
10