/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:



    vector<string> binaryTreePaths(TreeNode* root) {
        if(root==nullptr){
            return {};
        }

        if(root->right==nullptr&&root->left==nullptr){
            string s;
            s+=to_string(root->val);
            return s;
        }

        if(root->right==nullptr){
            vector<string> v=binaryTreePaths(root->left);
            vector<string> ret;
            for(string s:v){
                ret.push_back(to_string(root->val)+s);
            }
            return ret;
        }
        if(root->left==nullptr){
            vector<string> v=binaryTreePaths(root->right);
            vector<string> ret;
            for(string s:v){
                ret.push_back(to_string(root->val)+s);
            }
            return ret;
        }
        vector<string> v=binaryTreePaths(root->right);
        vector<string> ret;
        for(string s:v){
                ret.push_back(to_string(root->val)+s);
        }
        v=binaryTreePaths(root->left);
        for(string s:v){
                ret.push_back(to_string(root->val)+s);
        }
        return ret;
    }
};