[Leetcode] Path Sum

/** * 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) {        // Start typing your C/C++ solution below        // DO NOT write int main() function        return traverse(root, sum);    }        bool traverse(TreeNode* n, int sum)    {        if (!n) return false;                if (!n->left && !n->right)        {            if (sum - n->val == 0)                return true;        }                    return traverse(n->left, sum - n->val) || traverse(n->right, sum - n->val);    }};