leetcode-Binary Tree Paths

Difficulty:
Easy

Given a binary tree, return all root-to-leaf paths.

For example, given the following binary tree:

1
/   \
2     3
\
5

All root-to-leaf paths are:

["1->2->5", "1->3"]

/**
* 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 {
vector<string> res;
void binaryTreePaths(TreeNode *root,string path){
if(!root->left&&!root->right)
res.push_back(path+to_string(root->val));

if(root->left)
binaryTreePaths(root->left,path+ to_string(root->val)+"->");

if(root->right)
binaryTreePaths(root->right,path+to_string(root->val)+"->");
}
public:
vector<string> binaryTreePaths(TreeNode* root) {
if(!root)
return res;
string path;
binaryTreePaths(root,path);
return res;
}
};