'''class Solution {

public:

int sumOfLeftLeaves(TreeNode* root) {

if(!root)

return 0;

int sum=0;

if(root->left&&root->left->left==NULL&&root->left->right==NULL)

sum+=root->left->val;

int left=sumOfLeftLeaves(root->left);

int right=sumOfLeftLeaves(root->right);

sum+=left;

sum+=right;

return sum;

```
}
```

};