http://www.geeksforgeeks.org/morris-traversal-for-preorder/
1 #include <iostream> 2 #include <vector> 3 #include <algorithm> 4 #include <queue> 5 #include <stack> 6 #include <string> 7 #include <fstream> 8 #include <map> 9 using namespace std; 10 11 struct node { 12 int data; 13 struct node *left, *right; 14 node() : data(0), left(NULL), right(NULL) { } 15 node(int d) : data(d), left(NULL), right(NULL) { } 16 }; 17 18 void prints(node *root) { 19 while (root) { 20 if (root->left == NULL) { 21 cout << root->data << " "; 22 root = root->right; 23 } 24 else { 25 node* cur = root->left; 26 while (cur->right && cur->right != root) cur = cur->right; 27 if (cur->right == NULL) { 28 cout << root->data << " "; 29 cur->right = root; 30 root = root->left; 31 } 32 else { 33 cur->right = NULL; 34 root = root->right; 35 } 36 } 37 } 38 } 39 40 int main() { 41 node *root = new node(1); 42 root->left = new node(2); 43 root->right = new node(3); 44 root->left->left = new node(4); 45 root->left->right = new node(5); 46 root->right->left = new node(6); 47 root->right->right = new node(7); 48 root->left->left->left = new node(8); 49 root->left->left->right = new node(9); 50 root->left->right->left = new node(10); 51 root->left->right->right = new node(11); 52 prints(root); 53 return 0; 54 }