标签：false pre add return and ini values turn rmi
题目描述:
Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum.
For example:
Given the below binary tree andsum = 22,
5
/ 4 8
/ / 11 13 4
/ \ 7 2 1
return true, as there exist a root-to-leaf path5->4->11->2which sum is 22.
/** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: bool hasPathSum(TreeNode *root, int sum) { if(!root) return false; if(root->left == NULL && root->right == NULL){ if(root->val == sum) return true; else return false; } bool res = hasPathHelp(root,sum,0); return res; } bool hasPathHelp(TreeNode *root,int sum,int curSum){ if(!root) return false; if(root->left == NULL && root->right == NULL){ if(curSum + root->val == sum) return true; else return false; } return hasPathHelp(root->left,sum,curSum+root->val)||hasPathHelp(root->right,sum,curSum+root->val); } };
标签：false pre add return and ini values turn rmi
原文地址：http://www.cnblogs.com/xiuxiu55/p/6518625.html
