You've got array A , consisting of n integers and a positive integer k . Array A is indexed by integers from 1 to n . You need to permute the array elements so that value became minimal possible. In particular, it is allowed not to change order of elements at all.

输入描述:

The first line contains two integers n, k (2 ≤ n ≤ 3·105, 1 ≤ k ≤ min(5000, n - 1)). The second line contains n integers A[1], A[2], ..., A[n] ( - 109 ≤ A[i] ≤ 109), separate by spaces — elements of the array A.

输出描述:

Print the minimum possible value of the sum described in the statement.

备注:

In the first test one of the optimal permutations is 1 4 2. In the second test the initial order is optimal. In the third test one of the optimal permutations is 2 3 4 4 3 5.