您的位置:首页 > 其它

leetcode——112——Path Sum

2016-04-03 11:53 323 查看
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 and
sum = 22
,
5
/ \
4   8
/   / \
11  13  4
/  \      \
7    2      1

return true, as there exist a root-to-leaf path
5->4->11->2
which sum is 22.

/**
* 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:
bool hasPathSum(TreeNode* root, int sum) {

if (root == NULL)
return false;
else if (root->left == NULL && root->right == NULL && root->val == sum)
return true;
else {
return hasPathSum(root->left, sum-root->val) || hasPathSum(root->right, sum - root->val);
}
}

};
内容来自用户分享和网络整理,不保证内容的准确性,如有侵权内容,可联系管理员处理 点击这里给我发消息
标签: