
You are given an integer array nums and an integer k . You are asked to distribute this array into k subsets of equal size such that there are no two equal elements in the same subset.
A subset's incompatibility is the difference between the maximum and minimum elements in that array.
Return the minimum possible sum of incompatibilities of the k subsets after distributing the array optimally, or return -1 if it is not possible.
A subset is a group integers that appear in the array with no particular order.
1 <= k <= nums.length <= 16nums.length is divisible by k1 <= nums[i] <= nums.length