LeetCode 404. Sum of Left Leaves
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.
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
int sumOfLeftLeaves(TreeNode* root) { // 树的递归遍历
if(root==NULL) return 0;
if(root->left!=NULL&&root->left->left==NULL&&root->lef;
return sum;t->right==NULL)
sum+=root->left->val;
//if(root->left!=NULL)
sumOfLeftLeaves(root->left);
//if(root->right!=NULL)
sumOfLeftLeaves(root->right)
}
private:
int sum=0;
};