219. 存在重复元素 II

from typing import List


class Solution:
    def containsNearbyDuplicate(self, nums: List[int], k: int) -> bool:
        if k <= 0:
            return False

        memory = set()

        for i, num in enumerate(nums):
            if num in memory:
                return True

            if len(memory) >= k:
                memory.remove(nums[i - k])
            memory.add(num)
        return False