LeetCode[Tree]: Sum Root to Leaf Numbers

发布时间：2020-12-13 20:22:41 所属栏目：PHP教程来源：网络整理

导读：Given a binary tree containing digits from 0⑼ 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

Given a binary tree containing digits from 0⑼ 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.

这个题目很简单，可用递归做：

class Solution { public: int sumNumbers(TreeNode *root) { sum = 0; sumNumbers(root,0); return sum; } private: int sum; void sumNumbers(TreeNode *root,int num) { if (!root) return; num = num*10 + root->val; if (root->left == nullptr && root->right == nullptr) sum += num; if (root->left) sumNumbers(root->left,num); if (root->right) sumNumbers(root->right,num); } };

（编辑：李大同）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!