Given an array of distinct integers. The task is to count all the triplets such that sum of two elements equals the third element.

Example 1:
Input:
N = 4
arr[] = {1, 5, 3, 2}
Output: 2
Explanation: There are 2 triplets:
1 + 2 = 3 and 3 +2 = 5
Example 2:
Input:
N = 3
arr[] = {2, 3, 4}
Output: 0
Explanation: No such triplet exits
Your Task:
You don't need to read input or print anything. Your task is to complete the function countTriplet() which takes the array arr[] and N as inputs and returns the triplet count
Expected Time Complexity: O(N^{2})
Expected Auxiliary Space: O(1)
Constraints:
1 ≤ N ≤ 10^{3}
1 ≤ arr[i] ≤ 10^{5}

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