String to two fork tree Leetcode C + + implementation

struct TreeNode {int val;    Treenode* left;    treenode* right; explicit TreeNode (int x): Val (x), left (nullptr), right (nullptr) {}};void trimlefttrailingspaces (string &input) {i    Nput.erase (Input.begin (), Find_if (Input.begin (), Input.end (), [] (int ch) {return!isspace (CH); }));}        void Trimrighttrailingspaces (String &input) {input.erase (find_if (Input.rbegin (), Input.rend (), [] (int ch) {    return!isspace (CH); }). Base (), Input.end ());}    treenode* stringtotreenode (String input) {trimlefttrailingspaces (input);    Trimrighttrailingspaces (input);    input = Input.substr (1, Input.length ()-2);    if (Input.empty ()) {return nullptr;    } string Item;    StringStream SS;    SS.STR (input);    Getline (SS, Item, ', ');    Auto root = new TreeNode (Stoi (item));    Queue<treenode*> Nodequeue;    Nodequeue.push (root);        while (true) {treenode* node = Nodequeue.front ();        Nodequeue.pop ();     if (!getline (SS, Item, ', ')) {       Break        } trimlefttrailingspaces (item);            if (item! = "NULL") {int leftnumber = Stoi (item);            Node->left = new TreeNode (leftnumber);        Nodequeue.push (Node->left);        } if (!getline (SS, Item, ', ')) {break;        } trimlefttrailingspaces (item);            if (item! = "NULL") {int rightnumber = Stoi (item);            Node->right = new TreeNode (rightnumber);        Nodequeue.push (Node->right); }} return root;}    void Pre_order (treenode* root) {if (root = = nullptr) return;    cout << root->val << ",";    Pre_order (Root->left); Pre_order (root->right);}

String to two fork tree Leetcode C + + implementation