From 302a2f176dc05c03db959c292a4a41b2f23040fa Mon Sep 17 00:00:00 2001 From: Jidong Xiao Date: Fri, 11 Apr 2025 20:37:07 -0400 Subject: [PATCH] adding morris post order --- animations/trees/morris/morrisPostOrder.html | 425 +++++++++++++++++++ 1 file changed, 425 insertions(+) create mode 100644 animations/trees/morris/morrisPostOrder.html diff --git a/animations/trees/morris/morrisPostOrder.html b/animations/trees/morris/morrisPostOrder.html new file mode 100644 index 0000000..a6d5986 --- /dev/null +++ b/animations/trees/morris/morrisPostOrder.html @@ -0,0 +1,425 @@ + + + + + Morris Post‑Order Traversal Animation & Code Display + + + + + +

Morris Post-Order Traversal Visualization

+

This animation shows how the Morris post-order traversal algorithm works without using a stack or recursion. Click the "Next Step" button to run the animation.

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0. void postorderTraversal(TreeNode* root) {
+1.     TreeNode* current = root;
+2.     TreeNode* rightmost;
+3.     while (current != nullptr) {
+4.         if (current->left != nullptr) {
+5.             rightmost = current->left;
+6.             while (rightmost->right != nullptr && rightmost->right != current) {
+7.                 rightmost = rightmost->right;
+8.             }
+9.             if (rightmost->right == nullptr) {
+10.                 rightmost->right = current;
+11.                 current = current->left;
+12.             } else {
+13.                 rightmost->right = nullptr;
+14.                 reverseTraverseRightEdge(current->left);
+15.                 current = current->right;
+16.             }
+17.         } else {
+18.             current = current->right;
+19.         }
+20.     }
+21.     reverseTraverseRightEdge(root); // traverse the final right edge
+22.     return;
+23. }
+24. 
+25. TreeNode* reverse(TreeNode* head) {
+26.     TreeNode* prev = nullptr;
+27.     TreeNode* next = nullptr;
+28.     while (head != nullptr) {
+29.         next = head->right;
+30.         head->right = prev;
+31.         prev = head;
+32.         head = next;
+33.     }
+34.     return prev;
+35. }
+36. 
+37. void reverseTraverseRightEdge(TreeNode* head) {
+38.     TreeNode* tail = reverse(head);
+39.     TreeNode* current = tail;
+40.     while (current != nullptr) {
+41.         std::cout << current->val << " ";
+42.         current = current->right;
+43.     }
+44.     reverse(tail); // restore the original tree structure
+45. }
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+
+ Post-order traversal output: +
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