Given an array of positive integers. Find the length of the longest sub-sequence such that elements in the subsequence are consecutive integers, the consecutive numbers can be in any order.

Example 1:
Input:
N = 7
a[] = {2,6,1,9,4,5,3}
Output:
6
Explanation:
The consecutive numbers here
are 1, 2, 3, 4, 5, 6. These 6
numbers form the longest consecutive
subsquence.
Example 2:
Input:
N = 7
a[] = {1,9,3,10,4,20,2}
Output:
4
Explanation:
1, 2, 3, 4 is the longest
consecutive subsequence.
Your Task:
You don't need to read input or print anything. Your task is to complete the function findLongestConseqSubseq() which takes the array arr[] and the size of the array as inputs and returns the length of the longest subsequence of consecutive integers.
Expected Time Complexity: O(N).
Expected Auxiliary Space: O(N).
Constraints:
1 <= N <= 10^{5}
0 <= a[i] <= 10^{5}

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