Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. Please write comments if you find the above code/algorithm incorrect, or find other ways to solve the same problem. K Reverse In Linked List . Time Complexity: O(n) Given pointer to the head node of a linked list and a number K, the task is to reverse the first K nodes of the linked list. Discussions. Method 2 (Process k nodes and recursively call for rest of the list) Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. Let the pointer to the next node be. If the linked list has 0 or only 1 node, then it does not make sense to reverse the list, so we can simply return then and there. The kvalue is a positive integer and less than or equal to the length of linked list. Special care has to be taken while linking reversed groups with each other. Reverse the singly linked list and return the pointer/reference to the head of the reversed linked list. By using our site, you Below is image shows how the reverse function works: Below is the implementation of the above approach: edit You should first read the question and watch the question video. Special care has to be taken while linking reversed groups with each other. Don’t stop learning now. Don’t stop learning now. Given a Linked List, reverse the nodes of a linked list k at a time and return its modified list.. Interview prepration- Our coding bootcamp focusing on online coding challenges and competitive programming, delivered to. Now q points to (k+1)th node and we call the same procedure on it. Examples: Input: Head of following linked list 1->2->3->4->NULL Output: Linked list should be changed to, 4->3->2->1->NULL. Attention reader! If the number of nodes is not a multiple of k then left-out nodes in the end should remain as it is. Given pointer to the head node of a linked list, the task is to reverse the linked list. We need to reverse the list by changing the links between nodes. K reverse linked list: Given a singly linked list and an integer K, reverses the nodes of the list K at a time and returns modified linked list. It uses a third bool parameter b which decides whether to reverse the k elements or simply move the pointer. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready. Reverse a linked list from position m to n.Do it in one-pass. Please write comments if you find the above code/algorithm incorrect, or find other ways to solve the same problem. Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. In this C++ program to reverse a linked list in groups of given size we first need to partition linked list in groups of given size. In the given linked list, write a function to reverse every set of k nodes. #include using namespace std; class Node { public: int data; Node* next; }; Node *kAltReverse (Node *head, int k) { Node* ... edit. A common interview question asked at larger companies, reversing a linked list is a problem I’ve seen trip up a lot of engineers throughout my … Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready. How to reverse a singly linked list in C. Algorithm and steps to reverse a singly linked list. For the linked list 3 → 4 → 5 → 2 → 6 → 1 → 9 for kReverse(3) becomes 5 → 4→ 3→ 1→ 6→ 2→ 9→ 1 I am getting a 2. This challenge is part of a tutorial track by MyCodeSchool and is accompanied by a video lesson. Reverse a Linked List in groups of given size ‘K’ Example. We use cookies to ensure you have the best browsing experience on our website. Please write to us at contribute@geeksforgeeks.org to report any issue with the above content. If the nodes are not multiple of k then reverse the remaining nodes. Now, when our linked list is partitioned into groups, we need to reverse each group. close, link check also Reversal of a linked list Example: Input: 1->2->3->4->5->NULL Output: 5->4->3->2->1->NULL Follow up: A linked list can be reversed either iteratively or recursively. 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, Add two numbers represented by linked lists | Set 1, Add two numbers represented by linked lists | Set 2, Add Two Numbers Represented by Linked Lists | Set 3, Reverse a Linked List in groups of given size | Set 1, Reverse a Linked List in groups of given size | Set 2, Reverse alternate K nodes in a Singly Linked List, Alternate Odd and Even Nodes in a Singly Linked List, Alternating split of a given Singly Linked List | Set 1, Program for n’th node from the end of a Linked List, Find the middle of a given linked list in C and Java, Write a function that counts the number of times a given int occurs in a Linked List, Stack Data Structure (Introduction and Program), Doubly Linked List | Set 1 (Introduction and Insertion), Reverse alternate K nodes in a Singly Linked List - Iterative Solution, Given a linked list, reverse alternate nodes and append at the end, Convert singly linked list into circular linked list, Difference between Singly linked list and Doubly linked list, Convert Singly Linked List to XOR Linked List, C Program to reverse each node value in Singly Linked List, Reverse a singly Linked List in groups of given size | Set 3, Merge a linked list into another linked list at alternate positions, Append odd position nodes in reverse at the end of even positioned nodes in a Linked List, Delete all Prime Nodes from a Singly Linked List, Sum and Product of the nodes of a Singly Linked List which are divisible by K, Sum and Product of all Prime Nodes of a Singly Linked List, Product of the nodes of a Singly Linked List, Delete all Prime Nodes from a Circular Singly Linked List, Find the common nodes in two singly linked list, Count of Prime Nodes of a Singly Linked List, Sum and Product of the nodes of a Circular Singly Linked List which are divisible by K, Delete all Non-Prime Nodes from a Singly Linked List, Delete nodes which have a greater value on right side, Implement a stack using singly linked list, Delete a Linked List node at a given position, Implementing a Linked List in Java using Class, Circular Linked List | Set 1 (Introduction and Applications), Find Length of a Linked List (Iterative and Recursive), Write Interview For k = 3, you should return: 3->2->1->4->5. If the nodes are not multiple of k then reverse the remaining nodes. One of them requires knowledge of pointers and one of them is pretty straight forward. Reverse a Linked List using Iterative Solution. The value of k is always smaller or equal to the length of the linked list and it is always greater than 0. Advance this k times in a while loop and keep reversing the list. k is a positive integer and is less than or equal to the length of the linked list. Given pointer to the head node of a linked list and a number K, the task is to reverse the first K nodes of the linked list. Please use ide.geeksforgeeks.org, generate link and share the link here. (K is input value) Given a linked list, write a function to reverse every alternate k nodes (where k is an input to the function) in an efficient way. So method 1 uses two while loops and processes 2k nodes in one recursive call. Give the complexity of your algorithm. NOTE : The length of the list is divisible by K Example : Given linked list 1 -> 2 -> 3 -> 4 -> 5 -> 6 and K=2, You should return 2 -> 1 -> 4 -> 3 -> 6 -> 5 Try to solve the problem using constant extra space. Given a linked list, reverse the nodes of a linked list k at a time and return its modified list.. k is a positive integer and is less than or equal to the length of the linked list. You should first read the question and watch the question video. Find Complete Code at GeeksforGeeks Article: This video is contributed by komal kungwani Please Like, Comment and Share the Video among your friends.