Pairwise swap elements of a linked list by swapping data

PROBLEM :

Given a singly linked list, write a function to swap elements pairwise. For example, if the linked list is 1->2->3->4->5 then the function should change it to 2->1->4->3->5, and if the linked list is 1->2->3->4->5->6 then the function should change it to 2->1->4->3->6->5.

Input:

In this problem, method takes one argument: the head of the linked list. The function should not read any input from stdin/console.
The struct Node has a data part which stores the data and a next pointer which points to the next element of the linked list.
There are multiple test cases. For each test case, this method will be called individually.

Output:
Pairwise swap linked list elements .

Note: If you use "Test" or "Expected Output Button" use below example format

Example:
Input:
1
8
1 2 2 4 5 6 7 8

Output:
2 1 4 2 6 5 8 7


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SIMPLE c++ IMPLEMENTATION :
--------------------------------------------------------------------------------

/*
  Pairwise swap a linked list
  The input list will have at least one element
  node is defined as
  struct node
  {
     int data;
     struct node *next;
  }
*/

void pairWiseSwap(struct node *head)
{
   struct node *temp ;
   int swap ;
   temp=head ;
   
    while(temp!=NULL&&temp->next!=NULL)
    {
        swap=temp->data ;
        temp->data=temp->next->data ;
        temp->next->data=swap ;
       
        temp=temp->next->next ;
    }
   
}

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