Examples
Input: numbers = [4,4,4,6,6,5,5,5], k = 2
Output: [4,5]
Explanation: The two most frequent numbers are 4 and 5, as they appear the most often in the array.
Input: numbers = [7,7,7,8,8,9,9,9], k = 3
Output: [7,9,8]
Explanation: The three most frequent numbers are 7, 9, and 8.
Input: numbers = [10,10,10,10,10], k = 1
Output: [10]
Explanation: Since there is only one unique number, 10, it is the most frequent.