//404
Find the sum of all left leaves in a given binary tree.
Example:
3
/
9 20
/
15 7
There are two left leaves in the binary tree, with values 9 and 15 respectively. Return 24.
class Solution {
public:
int sumOfLeftLeaves(TreeNode* root) {
if(root==NULL){
return 0;
}
//left leaf,recursion root->right
if(root->left && !root->left->left && !root->left->right){
return root->left->val+sumOfLeftLeaves(root->right);
}
return sumOfLeftLeaves(root->left)+sumOfLeftLeaves(root->right);
}
};
