Leetcode 347. Top K Frequent Elements. Python (Bubble Sort)

Top K Frequent Elements

Given an integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order.

Example 1:

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

Example 2:

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

Constraints:

1 <= nums.length <= 105
-104 <= nums[i] <= 104
k is in the range [1, the number of unique elements in the array].
It is guaranteed that the answer is unique.

Follow up: Your algorithm's time complexity must be better than O(n log n), where n is the array's size.

Solution :

class Solution:

def topKFrequent(self, n: List[int], k: int) -> List[int]:

# [1,1,1,2,2,3] & k = 2

f = [[] for i in range(len(n) + 1)]

# f = [[], [3], [2], [1], [], [], []]

cnt = {}

ans = []

for i in n :

cnt[i] = 1 + cnt.get(i,0)

for i,j in cnt.items():

f[j].append(i)

for i in range(len(f) - 1, 0, -1):

for j in f[i] :

ans.append(j)

if len(ans) == k:

return ans

Explaination :

Comments

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