LeetCode题解之Binary Tree Paths

1、题目描述

2、分析

使用递归。

3、代码

vector<string> ans;
    
    vector<string> binaryTreePaths(TreeNode* root) {
         
        if (root == NULL) return ans;
        leafPath(root,"");
        return ans;
        
        
    }
    
    void leafPath(TreeNode *root, string s)
    {
        if (root == NULL)
            return ;
        if (root->left == NULL && root->right == NULL){
            string stmp = s + to_string(root->val);
            ans.push_back(stmp);
            return ;
        } else {
            string stmp = s  + to_string(root->val) + "->";
            leafPath(root->left, stmp);
            leafPath(root->right, stmp);
        }
        
    }