Given an Array of Integers Arr of length N, you have to count number of elements of the array that can be counted as pair of equal elements.

Example 1:
Input :
N = 7
Arr[] = {10, 10, 10, 20, 20, 10, 20}
Output:
6
Explanation:
The pairs formed are: (10,10),
(10,10), (20,20). The leftover 10
can't be paired with any other 10.
So, the Output is 6.
Example 2:
Input :
N = 4
Arr = {10, 20, 30, 40}
Output:
0
Explanation:
No pairs can be formed.
So, the Output is 0.

Your Task:
You don't need to read input or print anything. Your task is to complete the function getTwinCount() which takes an Integer N and an Array Arr as input and returns the answer.

Expected Time Complexity: O(N)
Expected Auxiliary Space: O(N)

Constraints:
1 <= N <= 10^{5}
1 ≤ Arr[i] ≤ 10^{5}

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