Reverse a Linked List in groups of given size.
Submissions: 31602   Accuracy:

45.83%

  Difficulty: Medium   Marks: 4

Given a linked list of size N. The task is to reverse every k nodes (where k is an input to the function) in the linked list.

Input:
First line of input contains number of testcases T. For each testcase, first line contains length of linked list and next line contains the linked list elements.

Output:
For each testcase, there will be a single line of output which contains the linked list with every k group elements reversed.

Example:
Input:
1
8
1 2 2 4 5 6 7 8
4

Output:
4 2 2 1 8 7 6 5

Explanation:
Testcase 2:
Since, k = 4. So, we have to reverse everty group of two elements. Modified linked list is as 4, 2, 2, 1, 8, 7, 6, 5.

 

** For More Input/Output Examples Use 'Expected Output' option **

Contributor: Harshit Sidhwa
Author: Karan Grover


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