Sum of Left Leaves

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.

30:00

Sum of Left Leaves

easy

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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: [3,9,20,null,null,15,7]

Output: 24

Constraints:

The number of nodes is in the range $[1, 1000]$ .
$-1000 \leq \text{Node.val} \leq 1000$

Input

arr =[3,9,20,null,null,15,7]

Find sum of all left leaves in the tree

Sum: 0

Current Node

Left Leaf

Visited

Binary Tree

3

9

L

20

15

L

7

Left Leaves Found

None yet

Sum of Left Leaves: 0

Variables

No variables to display

DepthFunction Call

Stack empty

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