LeetCode题解(1852)：Distinct Numbers in Each Subarray(Python)

题目：​​原题链接​​（中等）

标签：扫描线算法、哈希表、滑动窗口、数组

解法一：

class Solution:
    def distinctNumbers(self, nums: List[int], k: int) -> List[int]:
        ans = []
        count = collections.Counter(nums[:k])
        for i in range(len(nums) - k):
            ans.append(len(count))
            count[nums[i + k]] += 1
            count[nums[i]] -= 1
            if count[nums[i]] == 0:
                count.pop(nums[i])
        ans.append(len(count))
        return