Given an array of integers and a number k, write a function that returns true if given array can be divided into pairs such that sum of every pair is divisible by k.

Example 1 :
Input : arr = [9, 5, 7, 3], k = 6
Output: True
Explanation: {(9, 3), (5, 7)} is a
possible solution. 9 + 3 = 12 is divisible
by 6 and 7 + 5 = 12 is also divisible by 6.
Example 2:
Input : arr = [2, 4, 1, 3], k = 4
Output: False
Explanation: There is no possible solution.

Your Task:
You don't need to read or print anything. Your task is to complete the function canPair() which takes array and k as input parameter and returns true if array can be divided into pairs such that sum of every pair is divisible by k otherwise returns false.

Expected Time Complexity: O(n)
Expected Space Complexity : O(n)

Constraints:
1 <= length of array <= 10^5
1 <= elements of array <= 10^5
1 <= k <= 10^5

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