输入：nums = [1,2,3,1], k = 3
输出：true

输入：nums = [1,0,1,1], k = 1
输出：true

输入：nums = [1,2,3,1,2,3], k = 2
输出：false

public boolean containsNearbyDuplicate(int[] nums, int k) {
    Map<Integer, Integer> map = new HashMap<>();
    for (int i = 0; i < nums.length; i++) {
        if (map.containsKey(nums[i]) && i - map.get(nums[i]) <= k) {
            return true;
        } else {
            map.put(nums[i], i);
        }
    }
    return false;
}