Contains Duplicate II

class Solution {
public:
    bool containsNearbyDuplicate(vector<int>& nums, int k) {
        unordered_set<int> window;
        for (int i = 0; i < (int)nums.size(); ++i) {
            if (window.count(nums[i])) return true;
            window.insert(nums[i]);
            if ((int)window.size() > k) window.erase(nums[i - k]);
        }
        return false;
    }
};

func containsNearbyDuplicate(nums []int, k int) bool {
    window := map[int]bool{}
    for i, v := range nums {
        if window[v] {
            return true
        }
        window[v] = true
        if len(window) > k {
            delete(window, nums[i-k])
        }
    }
    return false
}

from typing import List

class Solution:
    def containsNearbyDuplicate(self, nums: List[int], k: int) -> bool:
        window = set()
        for i, v in enumerate(nums):
            if v in window:
                return True
            window.add(v)
            if len(window) > k:
                window.remove(nums[i - k])
        return False

function containsNearbyDuplicate(nums, k) {
    const window = new Set();
    for (let i = 0; i < nums.length; i++) {
        if (window.has(nums[i])) return true;
        window.add(nums[i]);
        if (window.size > k) window.delete(nums[i - k]);
    }
    return false;
}

class Solution {
    public boolean containsNearbyDuplicate(int[] nums, int k) {
        Set<Integer> window = new HashSet<>();
        for (int i = 0; i < nums.length; i++) {
            if (window.contains(nums[i])) return true;
            window.add(nums[i]);
            if (window.size() > k) window.remove(nums[i - k]);
        }
        return false;
    }
}

function containsNearbyDuplicate(nums: number[], k: number): boolean {
    const window = new Set<number>();
    for (let i = 0; i < nums.length; i++) {
        if (window.has(nums[i])) return true;
        window.add(nums[i]);
        if (window.size > k) window.delete(nums[i - k]);
    }
    return false;
}