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.
Solution:
/** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: int sum = 0; int calc(int cur_value, TreeNode *node) { if(node == NULL) return 0; if(node -> left == NULL && node -> right == NULL) { sum += cur_value * 10 + node -> val; } else { if(node -> left != NULL) calc(cur_value * 10 + node -> val, node -> left); if(node -> right != NULL) calc(cur_value * 10 + node -> val, node -> right); } } int sumNumbers(TreeNode *root) { calc(0, root); return sum; } };
[LeetCode] Sum Root to Leaf Numbers,布布扣,bubuko.com
[LeetCode] Sum Root to Leaf Numbers
原文：http://www.cnblogs.com/changchengxiao/p/3586337.html