98. Top K Frequent Elements

Given an integer array nums and an integer k, return any order list of the k most frequent elements in nums.

Your solution must run in better than O(n log n) time, where n = nums.length.

Example 1:

Input: nums = [1,1,1,2,2,3], k = 2

Output: [1,2]

Explanation: 1 appears 3 times, 2 appears 2 times, 3 appears once.

       The two most-frequent elements are 1 and 2.

Example 2:

Input: nums = [4,4,6,6,7], k = 2

Output: [4,6]

Explanation: 4 and 6 both occur twice (highest), 7 occurs once.

Now Your Turn!

Pick the correct output for the given input

Input: nums = [-1,-1,-2,-2,-2,-3], k = 1

Still unsure what the problem is asking ?

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Constraints:

  • 1 ≤ nums.length ≤ 105
  • -104 ≤ nums[i] ≤ 104
  • 1 ≤ k ≤ number of distinct elements in nums
  • The answer is guaranteed to be unique.

Fun Facts

0
class Solution {
public:
vector<int> topKFrequent(const vector<int>& nums, int k) {
// Your code goes here
}
};
Test Case

Input:

K
Nums
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