Given a non-empty array of integers, find the top k elements which have the highest frequency in the array. If two numbers have the same frequency then the larger number should be given preference. 

Example 1:

Input:
nums = {1,1,1,2,2,3},
k = 2
Output: {1, 2}

Example 2:

Input:
nums = {1,1,2,2,3,3,3,4},
k = 2
Output: {3, 2}
Explanation: Elements 1 and 2 have the
same frequency ie. 2. Therefore, in this
case, the answer includes the element 2
as 2 > 1.

User Task:
The task is to complete the function topK() that takes the array and integer k as input and returns a list of top k frequent elements.

Expected Time Complexity : O(NlogN)
Expected Auxilliary Space : O(N)

Constraints:
1 <= N <= 10³
1<=A[i]<=10⁴