Top K Frequent Elements

Problem Description Given an integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order. In the interview, you may first be asked to solve it with a brute-force/sorting approach, then optimize it using a heap / priority queue. Input Format For runnable testing, use the following input format: n nums[0] nums[1] ... nums[n-1] k Where: n is the length of the array; The second line contains n integers; The third line contains integer k. Output Format Print the k most frequent elements separated by spaces. The order of elements does not matter. For deterministic testing, the sample outputs below are shown in ascending order; in an interview, any valid order is usually acceptable. Constraints 1 <= n <= 10^5 -10^9 <= nums[i] <= 10^9 1 <= k <= number of distinct elements in nums The answer is guaranteed to be unique, or any valid ordering is accepted. Example Input 6 1 1 1 2 2 3 2 Output 1 2