347. Top K Frequent Elements[M]

https://leetcode.com/problems/top-k-frequent-elements/

Description

Given a non-empty array of integers, return the *k* most frequent elements.

Example 1:

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

Example 2:

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Input: nums = [1], k = 1
Output: [1]

Note:

  • You may assume k is always valid, 1 ≤ k ≤ number of unique elements.
  • Your algorithm’s time complexity must be better than O(n log n), where n is the array’s size.
  • It’s guaranteed that the answer is unique, in other words the set of the top k frequent elements is unique.
  • You can return the answer in any order.

Solution

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class Solution:
    def topKFrequent(self, nums: List[int], k: int) -> List[int]:
        counter = collections.Counter(nums)
        return [k for k,v in counter.most_common(k)]