Given an array of N integers. Find the first element that occurs at least K number of times.

Example 1:
Input :
N = 7, K = 2
A[] = {1, 7, 4, 3, 4, 8, 7}
Output :
4
Explanation:
Both 7 and 4 occur 2 times.
But 4 is first that occurs 2 times
As at index = 4, 4 has occurred
atleast 2 times whereas at index = 6,
7 has occurred atleast 2 times.

Your Task:
You don't need to read input or print anything. Your task is to complete the function firstElementKTime() which takes the array A[], its size N, and an integer K as inputs and returns the required answer. If the answer is not present in the array, return -1.
Expected Time Complexity: O(N)
Expected Auxiliary Space: O(N)
Constraints:
1 <= N <= 10^{4}
1 <= K <= 100
1<= A[i] <= 200

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