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---
title: '347. Top K Frequent Elements'
description: Given an integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order
sidebar:
label: 'Top K Frequent Elements'
badge: 'Medium'
---
<Badge variant="accent">Hash Table</Badge>
::::warning
Your algorithm's time complexity must be better than O(n log n), where n is the array's size.
::::
### Example 1:
- Input: `nums = [1,1,1,2,2,3], k = 2`
- Output: `[1,2]`
### Example 2:
- Input: `nums = [1], k = 1`
- Output: `[1]`
### Example 3:
- Input: `nums = [1,2,1,2,1,2,3,1,3,2], k = 2`
- Output: `[1,2]`
### Constraints:
- `1 <= nums.length <= 10^5`
- `-10^4 <= nums[i] <= 10^4`
- `k` is in the range `[1, the number of unique elements in the array]`.
- It is guaranteed that the answer is unique.
## Solution
```js
/**
* @param {number[]} nums
* @param {number} k
* @return {number[]}
*/
var topKFrequent = function (nums, k) {
const freq = {};
for (let n of nums) freq[n] = (freq[n] || 0) + 1;
return Object.keys(freq)
.map(Number)
.sort((a, b) => freq[b] - freq[a])
.slice(0, k);
};
```