Top K Frequent Elements

Problem Given an integer array nums and an integer k, return the k most frequent elements. The answer may be in any order.

Input / Output

• Input: array nums, integer k.
• Output: the k most frequent values.

Constraints

• 1 ≤ nums.length ≤ 10^5.
• k is in [1, number of distinct elements].
• The answer is guaranteed to be unique.

Example

• nums=[1,1,1,2,2,3], k=2 → [1,2]