Data Structure Binary Tree: Morris traversal for Preorder

http://www.geeksforgeeks.org/morris-traversal-for-preorder/

 #include <iostream>
 #include <vector>
 #include <algorithm>
 #include <queue>
 #include <stack>
 #include <string>
 #include <fstream>
 #include <map>
 using namespace std;

 struct node {
     int data;
     struct node *left, *right;
     node() : data(), left(NULL), right(NULL) { }
     node(int d) : data(d), left(NULL), right(NULL) { }
 };

 void prints(node *root) {
     while (root) {
         if (root->left == NULL) {
             cout << root->data << " ";
             root = root->right;
         }
         else {
             node* cur = root->left;
             while (cur->right && cur->right != root) cur = cur->right;
             if (cur->right == NULL) {
                 cout << root->data << " ";
                 cur->right = root;
                 root = root->left;
             }
             else {
                 cur->right = NULL;
                 root = root->right;
             }
         }
     }
 }

 int main() {
     node *root = new node();
     root->left = new node();
     root->right = new node();
     root->left->left = new node();
     root->left->right = new node();
     root->right->left = new node();
     root->right->right = new node();
     root->left->left->left = new node();
     root->left->left->right = new node();
     root->left->right->left = new node();
     root->left->right->right = new node();
     prints(root);
     return ;
 }