Sum Root to Leaf Numbers

Sum Root to Leaf Numbers

Total Accepted: 63531 Total Submissions: 202910 Difficulty: Medium

Given a binary tree containing digits from

0-9

only, each root-to-leaf path could represent a number.

An example is the root-to-leaf path

1->2->3

which represents the number

123

.

Find the total sum of all root-to-leaf numbers.

For example,

1
/ \
2   3

The root-to-leaf path

1->2

represents the number

12

.
The root-to-leaf path

1->3

represents the number

13

.

Return the sum = 12 + 13 =

25

.

(E) Path Sum (H) Binary Tree Maximum Path Sum

/**
* 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:
void sumNumbers(TreeNode* root,int &curSum,int num){
if(!root) return;
num = num*10+root->val;
if(root->left ==NULL && root->right ==NULL){
curSum += num;
return ;
}
sumNumbers(root->left,curSum,num);
sumNumbers(root->right,curSum,num);
}
int sumNumbers(TreeNode* root) {
int sum = 0;
sumNumbers(root,sum,0);
return sum;
}
};