# Description

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"]

The original problem is here.

The original code is here.

# My Solution

I solve this problem in C++, as below:

/*
*Binary Tree Paths
*Author: shuaijiang
*Email: zhaoshuaijiang8@gmail.com
*/
#include<iostream>
#include<vector>
#include<stdlib.h>
using namespace std;
/**
* 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:
vector<string> result;
vector<string> binaryTreePaths(TreeNode* root) {
string str;
TreePath(root, str);
return result;
}
void TreePath(TreeNode* root, string str){
if(root == NULL)
return;
stringstream ss;
string val;
ss<<root->val;
ss>>val;
ss.clear();
if(root->left == NULL && root->right == NULL){
if(str.size() == 0)
str += val;
else{
str.push_back('-');
str.push_back('>');
str += val;
}
result.push_back(str);
}
else{
if(root->left != NULL){
string str1 = str;
if(str1.size() == 0)
str1 += val;
else{
str1.push_back('-');
str1.push_back('>');
str1 += val;
}
TreePath(root->left, str1);
}
if(root->right != NULL){
string str2 = str;
if(str2.size() == 0)
str2 += val;
else{
str2.push_back('-');
str2.push_back('>');
str2 += val;
}
TreePath(root->right, str2);
}
}
}
};

# Note

To solve the problem, depth-first search was used.