1.二叉树的所有路径思路一:DFS /** * 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: void construct(TreeNode* p,string path,vector<string>& paths) {//字符串不需要引用,...