Find K most frequent elements

## Problem You are given an array of integers `nums` and an integer `k`. Return the `k` elements that occur most frequently in `nums`. You may return the answer in any order. ## Input - `nums`: list of integers (can include negatives) - `k`: integer where `1 <= k <= number of distinct values in nums` ## Output - A list of `k` integers corresponding to the most frequent values. ## Example - Input: `nums = [1,1,1,2,2,3]`, `k = 2` - Output: `[1,2]` ## Constraints (typical interview bounds) - `1 <= len(nums) <= 10^5` - Values fit in 32-bit signed integer ## Follow-ups (optional) - Can you do it faster than sorting by frequency?