Top K Frequent Elements

Code

O(N^2) : 108 ms, faster than 58.14% of Python3 online submissions

from collections import defaultdict

class Solution:
    def topKFrequent(self, nums, k):
        occurDict = defaultdict(int)
        for num in nums:
            occurDict[num] += 1
        occurList = [(freq, num) for num, freq in occurDict.items()]
        occurList.sort(reverse=True)
        return [num for freq, num in occurList][:k]

ans = Solution().topKFrequent([1,1,1,2,2,3], 2)
print(ans)