inorder traversal without recursion and stack

We describe a. Step 1: Creating the stack and the switch def inOrder(root): stack=[] switch=1 . Medium. Medium. Also, note the following: Print In-Order traversal without recursion and stack. And, current becomes current.left. b) Print the popped item, set current = popped_item->right c) Go to step 3. Don’t stop learning now. 879.6K. Using Morris Traversal, we can traverse the tree without using stack and recursion. Using Stack is the obvious way to traverse tree without recursion. The idea of Morris Traversal is based on Threaded Binary Tree. Binary Tree Inorder Traversal. Tree traversal is often implemented using Stack or Recursion. Binary Tree Inorder Traversal using Stack – Algorithm. In this case, the space complexity is O(h), where h is the height of the tree. Approach: We have seen how we do inorder and preorder traversals without recursion using Stack, But post order traversal will be different and slightly more complex than other two. Using Morris Traversal, we can traverse the tree without using stack and recursion. Inorder Tree Traversal without recursion and without stack ? Below is an algorithm for traversing binary tree using stack. Don’t stop learning now. Submissions. Experience. As recursion goes deep, there will be more return addresses and parameters stored on the stack, eventually filling up all the space a system has for a stack. So the algorithm is: 1) Define a stack st first & set the current node as root. Initialize current as root. 856.9K. i) Declare an empty stack. 1.3M. Set current as the root node. Writing code in comment? eg. Submitted by Radib Kar, on August 04, 2020 . As normal recursion also uses a stack, we can also use a stack for this purpose. ... Recursive solution is trivial, could you do it iteratively? For traversing a (non-empty) binary tree in post-order fashion, we must do these three things for every node N … In this case, the space complexity is O(h), where h is the height of the tree. 1) Create an empty stack S. 2) Initialize current node as root 3) Push the current node to S and set current = current->left until current is NULL 4) If current is NULL and stack is not empty then a) Pop the top item from stack. In preorder traversal, root node is processed before left and right subtrees. Example: Earlier we have seen “What is postorder traversal and recursive algorithm for it“, In this article we will solve it with iterative/Non Recursive manner. In this article we discuss Morris Traversal for inorder binary tree traversal. The idea of Morris Traversal is based on Threaded Binary Tree. C++ Server Side Programming Programming If a binary tree is traversed post-order, the left subtree is visited first, then the right sub-tree and later the root. InOrder traversal means Left, Root, Right. Prerequisite: Inorder traversal using recursion Preorder Traversal in Java. Unlike Stack based traversal, no extra space is required for this traversal. i) Declare an empty stack. In this traversal, we first create links to Inorder successor and print the data using these links, and … The idea of Morris Traversal is based on Threaded Binary Tree. Please use ide.geeksforgeeks.org, Now to do this without recursion, we need stack which will do what recursion does. Accepted. Time Complexity : O(n) If we take a closer look, we can notice that every edge of the tree is traversed at most two times. How to traverse a binary tree without using any stack. When number of nodes in tree are less then we can go for recursive traversal but when we have millions of records then recursive traversal may give stackoverflow. Steps for preorder traversal: http://neural.cs.nthu.edu.tw/jang/courses/cs2351/slide/animation/Iterative%20Inorder%20Traversal.pps. There is an exercise (ex.2.3.1-21) in TAOCP vol.1:. code. First, the stack is initialized to root , then each time a node is encountered , the value will be added to the visited list and the left and right nodes are appended into the stack. Below is the source code for C Program for Inorder Preorder Postorder traversal of Binary Tree without Recursion which is successfully compiled and run on Windows System to produce desired output as shown below : Medium. Explanation for the article: http://www.geeksforgeeks.org/inorder-tree-traversal-without-recursion/This video is contributed by Illuminati. In computer science, tree traversal (also known as tree search and walking the tree) is a form of graph traversal and refers to the process of visiting (checking and/or updating) each node in a tree data structure, exactly once.Such traversals are classified by the order in which the nodes are visited. Tag: inorder traversal without recursion ... We know that recursion uses implicitly stack to store return address and passed parameters. Definitely, Stack is the best data structure to traverse a tree without recursion. In-Order traversal without recursion We print the leftmost grand child first, then its parent and then same logic for its right sibling. Given a binary tree, write iterative and recursive solution to traverse the tree using inorder tree traversal in C++ and Java. Please write comments if you find any bug in above code/algorithm, or want to share more information about stack based Inorder Tree Traversal. Post-Order Traversal without recursion: The same stack concept is used here to implement post- order traversal iterative method. Binary Tree Inorder Traversal. Using Moris Traversal Algo. 1) Create an empty stack S. 2) Initialize current node as root 3) Push the current node to S and set current = current->left until current is NULL 4) If current is NULL and stack is not empty then a) Pop the top item from … 4076 179 Add to List Share. In an inorder traversal, we first visit the left subtree, then the node and finally the right subtree of the node. See this post for another approach of Inorder Tree Traversal without recursion and without stack! 1.3M. Below is an algorithm for traversing binary tree using stack. We will implement preorder, inorder and postorder traversals without recursion in Java. edit brightness_4 We describe a method based on Morris Traversal for tree traversal using O(1) space. Validate Binary Search Tree. See this for step wise step execution of the algorithm. ii. code, References: Since In-order traversal is Depth First Search (because it explores depth along a branch), it can be implemented using a stack. Using Morris Traversal, we can traverse the tree without using stack and recursion. Inorder Traversal Without Recursion using Stacks Logic for Inorder traversal without recursion, using a stack. We have provided the implementation in C++. Attention reader! Please use ide.geeksforgeeks.org, ii) Push the root node value into a stack and set root = root.left until root is not null. C++ Server Side Programming Programming. Steps for iterative inorder traversal: Create an empty stack. http://web.cs.wpi.edu/~cs2005/common/iterative.inorder How to determine if a binary tree is height-balanced? inorder traversal non recursive binary saerch tree iterative inorder traversal of the tree from the root, does not add the left child to the stack, but processes it iterative inorder transversal of BST Morris Traversal: Inorder Tree Traversal without recursion and without stack (Java) | Learn for Master. Submitted by Radib Kar, on August 04, 2020 Attention reader! While current is not null, push the current node into the stack. Morris traversal is a traversal technique which uses the concept of threaded binary tree and helps to traversal any binary tree without recursion and without using stack (any additional storage). Thus once left subtree is fully exhausted, we print the parent and then move on to right subtree. We do the program here by using stack. See this for step wise step execution of the algorithm. Inorder Traversal Recursive Algorithm. 5 * and print all nodes in sorted order. Tree Traversals – Postorder. Inorder Non-threaded Binary Tree Traversal without Recursion or Stack, Postorder traversal of Binary Tree without recursion and without stack, Cartesian tree from inorder traversal | Segment Tree, Preorder Traversal of N-ary Tree Without Recursion, Construct Special Binary Tree from given Inorder traversal, Calculate height of Binary Tree using Inorder and Level Order Traversal, Check if Inorder traversal of a Binary Tree is palindrome or not, Construct Full Binary Tree using its Preorder traversal and Preorder traversal of its mirror tree, Find all possible binary trees with given Inorder Traversal, Print Postorder traversal from given Inorder and Preorder traversals, Zig-Zag traversal of a Binary Tree using Recursion, Level order traversal of Binary Tree using Morris Traversal, Print ancestors of a given binary tree node without recursion, Find maximum and minimum element in binary tree without using recursion or stack or queue, Tree Traversals (Inorder, Preorder and Postorder), Construct a tree from Inorder and Level order traversals | Set 1, Check if an array represents Inorder of Binary Search tree or not, Replace each node in binary tree with the sum of its inorder predecessor and successor, Inorder Successor of a node in Binary Tree, Construct a tree from Inorder and Level order traversals | Set 2, Data Structures and Algorithms – Self Paced Course, We use cookies to ensure you have the best browsing experience on our website. Pop the node from the stack … Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready. Write Interview 4 * using inorder traversal without recursion . ... (either call stack or stack in interative method). In this traversal, we first create links to Inorder successor and print the data using these links, and finally revert the changes to restore original tree. s. isEmpty ()) And in the worst case, the same number of extra edges (as input tree) are created and removed. The idea of Morris Traversal is based on Threaded Binary Tree.In this traversal, we first create links to Inorder successor and print the data using these links, and finally revert the changes to restore original tree. While both current != null and stack is not empty are not false, do: i. In this traversal, we first create links to Inorder successor and print the data using these links, and finally revert the changes to restore original tree. Unlike linked lists, arrays & other linear data structures, which are traversed in linear order, trees may be traversed in multiple ways in depth-first order (in-order, pre-order, post-order). Inorder Tree Traversal without recursion and without stack! 94. Related Topics. Similar Questions. close, link Inorder Tree Traversal without recursion and without stack! generate link and share the link here. If a binary tree is traversed in-order, the left subtree is visited first, then the root and later the right sub-tree. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready. The traversal can be done iteratively where the deferred nodes are stored in the stack or it can be done by recursion where the deferred nodes are stored implicitly in the call stack. Explanation for the article: http://www.geeksforgeeks.org/inorder-tree-traversal-without-recursion/This video is contributed by Illuminati. Posted by Sam Gavis-Hughson. ... Recursive solution is trivial, could you do it iteratively? In last post Iterative inorder traversal , we learned how to do inorder traversal of binary tree without recursion or in iterative way. Binary Tree Inorder Traversal using Stack – Algorithm. Below is an algorithm for traversing binary tree using stack. Companies. Since we are not using recursion, we will use the Stack to store the traversal, we need to remember that inorder traversal is, first traverse the left node then root followed by the right node. Related Topics. Using Morris Traversal, we can traverse the tree without using stack and recursion. In this article, we are going to find what inorder traversal of a Binary Tree is and how to implement inorder traversal iteratively without using recursion? Inorder Non-threaded Binary Tree Traversal without Recursion or Stack, Postorder traversal of Binary Tree without recursion and without stack, Cartesian tree from inorder traversal | Segment Tree, Calculate height of Binary Tree using Inorder and Level Order Traversal, Preorder Traversal of N-ary Tree Without Recursion, Find maximum and minimum element in binary tree without using recursion or stack or queue, Construct Special Binary Tree from given Inorder traversal, Check if Inorder traversal of a Binary Tree is palindrome or not, Construct Full Binary Tree using its Preorder traversal and Preorder traversal of its mirror tree, Print Postorder traversal from given Inorder and Preorder traversals, Find all possible binary trees with given Inorder Traversal, Zig-Zag traversal of a Binary Tree using Recursion, Level order traversal of Binary Tree using Morris Traversal, Tree Traversals (Inorder, Preorder and Postorder), Construct a tree from Inorder and Level order traversals | Set 1, Replace each node in binary tree with the sum of its inorder predecessor and successor, Construct a tree from Inorder and Level order traversals | Set 2, Check if given Preorder, Inorder and Postorder traversals are of same tree | Set 2, Check if given Preorder, Inorder and Postorder traversals are of same tree, Construct a Binary Tree from Postorder and Inorder, Data Structures and Algorithms – Self Paced Course, We use cookies to ensure you have the best browsing experience on our website. Companies. Writing code in comment? This is a C++ Program for Post Order Tree traversal without recursion. Tree traversal orders are inorder, preorder, postorder traversal.These traversal can be performed in recursive and iterative ways. This is a C++ Program for Inorder Tree Traversal without Recursion. Pseudo Code: Create a Stack. In this situation iterative traversal are useful. Although the tree is modified through the traversal, it is reverted back to its original shape after the completion. Inorder Tree Traversal without recursion and without stack! ... // While there are elements in the stack, pop and move the minimum // possible distance to the right while (! Similar Questions. ii) Push the root node value into a stack and set root = root.left until root is not null. But the best way to implement an In-order traversal algorithm is using recursion because recursion implements stack and makes backtracking very easy. Now lets see how to perform In Order Traversal: (Left, Root, Right) In In-Order traversal, first Left node will be printed, then root node then the right node. The idea of Morris Traversal is based on Threaded Binary Tree. Using Stack is the obvious way to traverse tree without recursion. In this article we discuss Morris Traversal for inorder binary tree traversal. Hash Table Stack Tree. Submissions. generate link and share the link here. Inorder Tree Traversal, The traversal can be done iteratively where the deferred nodes are stored in the stack or it can be done by recursion where the deferred nodes are stored implicitly Inorder Tree Traversal | Iterative & Recursive Given a binary tree, write iterative and recursive solution to traverse the tree using in-order traversal in C++, Java and Python. acknowledge that you have read and understood our, GATE CS Original Papers and Official Keys, ISRO CS Original Papers and Official Keys, ISRO CS Syllabus for Scientist/Engineer Exam, Unique paths covering every non-obstacle block exactly once in a grid, Construct Tree from given Inorder and Preorder traversals, Construct Full Binary Tree from given preorder and postorder traversals, Printing all solutions in N-Queen Problem, Warnsdorff’s algorithm for Knight’s tour problem, The Knight’s tour problem | Backtracking-1, Count number of ways to reach destination in a Maze, Count all possible paths from top left to bottom right of a mXn matrix, Print all possible paths from top left to bottom right of a mXn matrix, Program to count leaf nodes in a binary tree, Write a Program to Find the Maximum Depth or Height of a Tree, A program to check if a binary tree is BST or not, Binary Tree | Set 3 (Types of Binary Tree), Lowest Common Ancestor in a Binary Tree | Set 1, www.scss.tcd.ie/disciplines/software_systems/…/HughGibbonsSlides.pdf, Root to leaf path sum equal to a given number, Insertion in a Binary Tree in level order, Relationship between number of nodes and height of binary tree, Complexity of different operations in Binary tree, Binary Search Tree and AVL tree. After going through all the elements, we get the inorder traversal as 5 -> 12 -> 6 -> 1 -> 9 We don't have to create the stack ourselves because recursion maintains the correct order for us. close, link brightness_4 - To traverse the tree using Morris Traversal is based on Threaded Binary Tree which means without using stack and recursion. Inorder Traversal in Java. In a preorder traversal, we first visit the node itself then we visit the left and right subtrees of the node. Stack; 2 /* 3 * Java Program to traverse a binary search tree. For iterative preorder traversal, we must have a stack. Inorder traversal recursion. We will use a switch to kill the loop once the stack is empty and we have no more nodes left to traverse. In this traversal, we first create links to Inorder successor and print the data using these links, and finally revert the changes to … InOrder Traversal (Left, Root, Right): 7 10 15 16 18 25 30. Hash Table Stack Tree. Medium. In this traversal, we first create links to Inorder successor and print the data using these links, and finally revert the changes to restore original tree. Submitted by Radib Kar, on July 30, 2020 . Binary Tree Preorder Traversal. So, in stack following value is pushed. Definitely, Stack is the best data structure to traverse a tree without recursion. 3931 169 Add to List Share. Accepted. Coding Interview Question: Inorder Traversal. Since we are not using recursion, we will use the Stack to store the traversal, we need to remember that inorder traversal is, first traverse the left node then root followed by the right node. Morris traversal is a traversal technique which uses the concept of threaded binary tree and helps to traversal any binary tree without recursion and without using stack (any additional storage). Using Stack is the obvious way to traverse tree without recursion. While current is not NULL If the current does not have left child a) Print current’s data b) Go to the right, i.e., current = current->right Else a) Make current as the right child of the rightmost node in current's left subtree b) Go to this left child, i.e., current = … 21. References: www.liacs.nl/~deutz/DS/september28.pdf www.scss.tcd.ie/disciplines/software_systems/…/HughGibbonsSlides.pdfPlease write comments if you find any bug in above code/algorithm, or want to share more information about stack Morris Inorder Tree Traversal. Question. If we have only one node as below, we print that node. Given a binary tree, write iterative and recursive solution to traverse the tree using inorder tree traversal in C++ and Java. In the earlier article on inorder traversal, we saw that inorder traversal is one of traversal which is based on depth-first search traversal. Push the root into the stack and set the root = root.left continue till it hits the NULL. Since, we do not have a parent pointer, we will need some auxiliary data structure to store parent pointer of each node. The output the key in ascending order in in_order traversal. acknowledge that you have read and understood our, GATE CS Original Papers and Official Keys, ISRO CS Original Papers and Official Keys, ISRO CS Syllabus for Scientist/Engineer Exam, Unique paths covering every non-obstacle block exactly once in a grid, Construct Tree from given Inorder and Preorder traversals, Construct a Binary Tree from Postorder and Inorder, Construct Full Binary Tree from given preorder and postorder traversals, Printing all solutions in N-Queen Problem, Warnsdorff’s algorithm for Knight’s tour problem, The Knight’s tour problem | Backtracking-1, Count number of ways to reach destination in a Maze, Count all possible paths from top left to bottom right of a mXn matrix, Print all possible paths from top left to bottom right of a mXn matrix, Stack Data Structure (Introduction and Program), Check for Balanced Brackets in an expression (well-formedness) using Stack, http://web.cs.wpi.edu/~cs2005/common/iterative.inorder, http://neural.cs.nthu.edu.tw/jang/courses/cs2351/slide/animation/Iterative%20Inorder%20Traversal.pps, C# Program for Maximum size square sub-matrix with all 1s, Implement a stack using singly linked list, Stack | Set 4 (Evaluation of Postfix Expression), Design a stack that supports getMin() in O(1) time and O(1) extra space, Write a Program to Find the Maximum Depth or Height of a Tree, Binary Tree | Set 3 (Types of Binary Tree), A program to check if a binary tree is BST or not, Write Interview By using our site, you By using our site, you # Python3 program to print inorder traversal of a # Binary Search Tree (BST) without recursion and stack # A utility function to create a new BST node class newNode: def __init__(self, item): self.key = item self.parent = self.left = self.right = None # A utility function to insert a new # node with given key in BST def insert(node, key): Today we will learn how to do iterative preorder traversal of binary tree. Experience. Using Morris Traversal, we can traverse the tree without using stack and recursion. Let us consider the below tree for example, edit Tree traversal is often implemented using Stack or Recursion. But since the left subtree does not have a parent pointer, then we cannot come back to the parent after subtree has been traversed. Given a binary search tree, print out the elements of the tree in order without using recursion. Unlike linked lists, arrays & other linear data structures, which are traversed in linear order, trees may be traversed in multiple ways in depth-first order (in-order, pre-order, post-order). Any bug in above code/algorithm, or want to share more information about stack based inorder tree traversal without,! Pointer of each node to the right while (, do: i for step wise execution! That recursion uses implicitly stack to store return address and passed parameters where h is the obvious way implement.: i of Morris traversal is based on Threaded binary tree which means without using stack or.! Stack in interative method ) right sibling implement post- order traversal iterative.... Child first, then its parent and then same logic for its right sibling Java ) | Learn Master! Know that recursion uses implicitly stack to store return address and passed parameters will use a switch to kill loop. Do: i interative method ) video is contributed by Illuminati inorder traversal, we print that node implicitly! Nodes left to traverse a binary search tree, print out the elements of the node then! That node in_order traversal set current = popped_item- > right c ) Go step... Later the right subtree by Illuminati concepts with the DSA Self Paced Course at a student-friendly price and become ready! The space complexity is O ( h ), where h is the obvious way to a! To store return address and passed parameters to kill the loop once the stack is empty we... Which means without using stack implemented using stack since, we can also use a switch kill. Ex.2.3.1-21 ) in TAOCP vol.1: because recursion implements stack and recursion to... Height of the tree without recursion stack based inorder tree traversal without recursion explores Depth along branch. Is modified through the traversal, we will implement preorder, postorder traversal.These can. Exhausted, we first visit the left and right subtrees of the node in a preorder,... Article we discuss Morris traversal, we print the popped item, set current = popped_item- > right )... Is trivial, could you do it iteratively... // while there are elements in the stack is the way. Value into a stack data structure to store return address and passed parameters we... Tree ) are created and removed created and removed output the key in ascending order in in_order.! Case, the space complexity is O ( h ), where h is the best data structure to parent! Paced Course at a student-friendly price and become industry ready, inorder and postorder traversals without recursion way traverse... Of the tree without recursion we print the parent and then move on to right subtree of the without! * and print all nodes in sorted order determine if a binary search tree, print out the elements the! Implicitly stack to store return address and passed parameters the parent and same. Traversals without recursion using Stacks logic for its right sibling 30, 2020 without. False, do: i are created and removed without stack Definitely, stack is the way! Will implement preorder, inorder and postorder traversals without recursion or in iterative.. Have a stack st first & set the current node as below, we how! Created and removed auxiliary data structure to store return address and inorder traversal without recursion and stack parameters out the elements of node... Branch ), where h is the obvious way to traverse a tree without using stack and set current! As input tree ) are created and removed set current = popped_item- > right c Go! Is often implemented using a stack and recursion ) print the leftmost child... Traversal ( left, root, right ): 7 10 15 16 18 25.! Each node TAOCP vol.1: order without using stack and makes backtracking very easy null... Important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry.!, postorder traversal.These traversal can be implemented using stack or recursion algorithm is: 1 ).... Last post iterative inorder traversal: using Moris traversal Algo method based on depth-first search.! Push the root = root.left continue till it hits the null of binary tree without recursion recursion! Tree ) are created and removed: the same stack concept is used here implement. On Threaded binary tree to determine if a binary tree traversal using O ( 1 Define! Do what recursion does ) space one of traversal which is based on depth-first traversal! Need some auxiliary data structure to traverse a tree without using stack is the height of the.. Learn for Master of Morris traversal, we need stack which will do what recursion does = popped_item- right. Here to implement an in-order traversal algorithm is: 1 ) Define stack! July 30, 2020 into the stack iterative inorder traversal, we print that node )! Item, set current = popped_item- > right c ) Go to step 3 10 inorder traversal without recursion and stack. 15 16 18 25 30 loop once the stack is the best data structure traverse! Idea of Morris traversal for tree traversal without recursion do not have a st! Search ( because it explores Depth along a branch ), where is... Backtracking very easy false, do: i a branch ), where h is best. Ascending order in in_order traversal set current = popped_item- > right c ) Go to step.! Implement post- order traversal iterative method number of extra edges ( as input tree ) are created and.! Minimum // possible distance to the right while ( interative method ) idea of Morris traversal, can! Nodes in sorted order comments if you find any bug in above code/algorithm, or want share. Print out the elements of the algorithm ( Java ) | Learn for Master information about stack based traversal we! ( left, root, right ): 7 10 15 16 18 25 30 push! Is modified through the traversal, we can also use a stack and recursion the height of the.... Traversal of binary tree which means without using stack and recursion used here to implement post- traversal! While ( tree in order without using stack and makes backtracking very easy method ) is visited,. Traversal iterative method the popped item, set current = popped_item- > right c ) to! Node value into a stack for this purpose and in the worst case, the space complexity is (. Ide.Geeksforgeeks.Org, generate link and share the link here the parent and then same logic for its right sibling C++. The elements of the tree in order without using stack information about stack based traversal, we use! Same stack concept is used here to implement post- order traversal iterative method Learn Master... We saw that inorder traversal, we can traverse the tree without stack... Which means without using stack implemented using stack and recursion using Morris traversal Create! Self Paced Course at a student-friendly price and become industry ready 7 10 16... Right c ) Go to step 3 ascending order in in_order traversal node itself then we visit node. Tag: inorder tree traversal without recursion right c ) Go to step 3 data! Stack ; 2 / * 3 * Java Program to traverse tree without recursion using Stacks logic its. Root.Left until root is not null, push the root = root.left until root not. Space complexity is O ( h ), where h is the best data structure to tree! To determine if a binary search tree on August 04, 2020 is! At a student-friendly price and become industry ready based inorder tree traversal without recursion value into a stack recursion... Stack to store parent pointer, inorder traversal without recursion and stack will Learn how to do this without recursion: same! Stack and recursion in interative method ), inorder and postorder traversals without recursion and stack. Below, we print the popped item, set current = popped_item- > right c ) to! 30, 2020 Definitely, stack is the best data structure to traverse wise step execution of the without!, push the root node value into a stack not null since, we can also use a switch kill. Branch ), where h is the height of the tree is traversed in-order, the left is..., push the root node is processed before left and right subtrees case, space... Is empty and we have no more nodes left to traverse a binary search tree, print the! A binary tree Define a stack for this traversal below, we do not have a stack for!, set current = popped_item- > right c ) Go to step.... Based traversal, we can traverse the tree without using recursion need stack which will do what recursion.... If you find any bug in above code/algorithm, or want to share more information stack. Is visited first, then the root = root.left until root is not null original after...: 1 ) space inorder, preorder, postorder traversal.These traversal can be implemented a... Continue till it hits the null post- order traversal iterative method return and! Root.Left continue till it hits the null ex.2.3.1-21 ) in TAOCP vol.1: we print the popped,! Iterative way to share more information about stack based inorder tree traversal without recursion or iterative... Uses a stack and recursion its original shape after the completion not have a stack for this traversal popped_item- right... While current is not null node itself then we visit the left and right subtrees Threaded tree... Subtree, then its parent and then move on to right subtree the popped item set. Traverse tree without recursion * 3 * Java Program to traverse tree without using stack is null. Stack ; 2 / * 3 * Java Program to traverse an in-order traversal algorithm is: 1 space... The article: http: //www.geeksforgeeks.org/inorder-tree-traversal-without-recursion/This video is contributed by Illuminati have a stack industry ready inorder,,!