Remove every k-th node of the linked list
- Difficulty Level : Easy
- Last Updated : 26 Jul, 2022
Given a singly linked list, Your task is to remove every K-th node of the linked list. Assume that K is always less than or equal to length of Linked List.
Input : 1->2->3->4->5->6->7->8 k = 3 Output : 1->2->4->5->7->8 As 3 is the k-th node after its deletion list would be 1->2->4->5->6->7->8 And now 4 is the starting node then from it, 6 would be the k-th node. So no other kth node could be there.So, final list is: 1->2->4->5->7->8. Input: 1->2->3->4->5->6 k = 1 Output: Empty list All nodes need to be deleted
The idea is to traverse the list from the beginning and keep track of nodes visited after the last deletion. Whenever count becomes k, delete the current node and reset the count as 0.
(1) Traverse list and do following (a) Count node before deletion. (b) If (count == k) that means current node is to be deleted. (i) Delete current node i.e. do // assign address of next node of // current node to the previous node // of the current node. prev->next = ptr->next i.e. (ii) Reset count as 0, i.e., do count = 0. (c) Update prev node if count != 0 and if count is 0 that means that node is a starting point. (d) Update ptr and continue until all k-th node gets deleted.
Below is the implementation.
1 2 1
Time Complexity : O(n)
Auxiliary Space : O(1)
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