Given an array arr of n positive integers. The task is to swap every i^{th} element of the array with (i+2)^{th} element.
Note: When passing array to function, we basically pass the reference to the array. More details here. We'll learn more about pointers and references in upcoming module.
Example:
Input:
n = 5
arr[] = 1 2 3 4 5
Output:
3 4 5 2 1
Explanation:
Swapping 1 and 3, makes the array 3 2 1 4 5.
Now, swapping 2 and 4, makes the array
3 4 1 2 5. Again,swapping 1 and 5, makes the
array 3 4 5 2 1.
Your Task:
Your task is to complete the function swapElements(), which should swap each ith element with (i+2)^{th} element. No need to print or return the array.

Expected Time Complexity: O(n)
Expected Auxilary Space: O(1)
Constraints:
1 <= N <= 10^{6}
1 <= A_{i} <= 10^{6}

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