class Solution:

    def containsNearbyDuplicate(self, nums: List[int], k: int) -> bool:

        for i in range(len(nums)-1):

            for j in range(i+1,min(i+k+1,len(nums))):

                if nums[i] == nums[j]:return True

        return False

class Solution:

    def containsNearbyDuplicate(self, nums: List[int], k: int) -> bool:

        if k>=len(nums):

            if len(set(nums))!=len(nums):

                return True

        else:

            for i in range(len(nums)-k):

                if len(set(nums[i:i+k+1]))!=len(nums[i:i+k+1]):return True

        return False

class Solution:

    def containsNearbyDuplicate(self, nums: List[int], k: int) -> bool:

        windows = set()

        for i in range(len(nums)):

            if nums[i] in windows:

                return True

            windows.add(nums[i])

            if len(windows) > k:

                windows.remove(nums[i-k])

        return False