Easy Java Recursion Solution

```
public class Solution {
public int sumOfLeftLeaves(TreeNode root) {
return rightSum(root);
}
private int leftSum(TreeNode node) {
if (node == null)
return 0;
if (node.left == null && node.right == null)
return node.val;
return leftSum(node.left) + rightSum(node.right);
}
private int rightSum(TreeNode node) {
if (node == null || (node.left == null && node.right == null))
return 0;
return leftSum(node.left) + rightSum(node.right);
}
}
```