Maximum Sum of Distinct Subarrays With Length K

You are given an integer array `nums` and an integer `k`. Find the maximum subarray sum of all the subarrays of `nums` that meet the following conditions: - The length of the subarray is `k`, and - All the elements of the subarray are **distinct**. Return _the maximum subarray sum of all the subarrays that meet the conditions__._ If no subarray meets the conditions, return `0`. _A **subarray** is a contiguous non-empty sequence of elements within an array._   **Example 1:** **Input:** nums = [1,5,4,2,9,9,9], k = 3 **Output:** 15 **Explanation:** The subarrays of nums with length 3 are: - [1,5,4] which meets the requirements and has a sum of 10. - [5,4,2] which meets the requirements and has a sum of 11. - [4,2,9] which meets the requirements and has a sum of 15. - [2,9,9] which does not meet the requirements because the element 9 is repeated. - [9,9,9] which does not meet the requirements because the element 9 is repeated. We return 15 because it is the maximum subarray sum of all the subarrays that meet the conditions ``` **Example 2:** **Input:** nums = [4,4,4], k = 3 **Output:** 0 **Explanation:** The subarrays of nums with length 3 are: - [4,4,4] which does not meet the requirements because the element 4 is repeated. We return 0 because no subarrays meet the conditions. ```   **Constraints:** - `1 <= k <= nums.length <= 105` - `1 <= nums[i] <= 105`