Given an integer array nums and an integer k,
return the maximum sum of a non-empty subset of that array such that
for every two consecutive integers in the subset, nums[i] and nums[j],
where i < j, the condition j - i <= k is
satisfied.
A subset of an array is obtained by deleting some number of elements (can be zero) from the array, leaving the remaining elements in their original order.
Example 1:
Input: nums = [10,2,-10,5,20], k = 2 Output: 37 Explanation: The subset is [10, 2, 5, 20].
Example 2:
Input: nums = [-1,-2,-3], k = 1 Output: -1 Explanation: The subset must be non-empty, so we choose the largest number.
Example 3:
Input: nums = [10,-2,-10,-5,20], k = 2 Output: 23 Explanation: The subset is [10, -2, -5, 20].
Constraints:
1 <= k <= nums.length <= 10^5-10^4 <= nums[i] <= 10^4