Watch 10 video solutions for Sum of Left Leaves, a easy level problem involving Tree, Depth-First Search, Breadth-First Search. This walkthrough by Kevin Naughton Jr. has 25,663 views views. Want to try solving it yourself? Practice on FleetCode or read the detailed text solution.
Given the root of a binary tree, return the sum of all left leaves.
A leaf is a node with no children. A left leaf is a leaf that is the left child of another node.
Example 1:
Input: root = [3,9,20,null,null,15,7] Output: 24 Explanation: There are two left leaves in the binary tree, with values 9 and 15 respectively.
Example 2:
Input: root = [1] Output: 0
Constraints:
[1, 1000].-1000 <= Node.val <= 1000